This post is part of our special coverage Egypt Revolution 2011.

Tahrir Square was the scene of a brutal crackdown on the night of the biggest protest since Mubarak's ousting, which seemed to have revived the spirit of the revolution, harking back to some of the darkest Friday nights of the country's 18 days of protest.

The situation already looked tense, as a clump of several thousand protesters were digging in for an overnight sit-in around several army officers who had denounced the military council, after unprecedented demonstrations in front of the Israeli embassy had taken place earlier in the day.

Abdelrahman Hassan made a furtive wish, but it wasn't meant to be:

@estr4ng3d: I hope #tahrir makes it safely through the night.

Armed crackdown during the night

Security forces began deploying around the sit-in, completely surrounding the protesters. An armed assault took place at about 3:30am, clearing the square under heavy gunfire:

This street level YouTube video from Amr Bassiouny was reportedly taken right before the ring of troops attacked protesters:

@AmrBassiouny: Military and amn markazy sorrounding the area. Getting very tense. #Tahrir

@AmrBassiouny: #tahrir garden is completely sorrounded by heavily armed troops

The assault that followed was recorded in a series of long range overhead videos of the eerily lit Tahrir Square, uploaded promptly to YouTube by user Kikhote. The following video shows security forces assaulting protesters and taking down the tent that had reportedly housed the soldiers who had joined them. Continuous gunfire is audible:

@hambaka: Riot Police attacking us with tasers to disperse the people.. #tahrir http://plixi.com/p/90698768

@Linaattalah: Heard shots over phone with @ahmadshokr . seems intense and continuous. #tahrir

@meshelmay: gunfire just below my window — back in the bathroom. hiding.

@meshelmay: Kitchen vantage point: military has completely encircled Tahrir Square. Can hear protesters in the distance. Ugh & now, more gunfire..

@meshelmay: riot police marching chanting Allahu Akbar.

Jan25 Voices, a phone-to-tweet service set up during the shortlived Internet blackout, was put in use again, as a caller described the assault by the security forces:

@jan25voices:  LPC: We had joined hands saying ‘we are one’ to protect the army officers who were protesting with us in #Tahrir #Egypt

@jan25voices: LPC #Tahrir: Security forces came from near Cairo museum. Shots fired into the air.

@jan25voices: LPC: The army captured the soldiers who were protesting with us in #Tahrir and have taken them. There were injuries. #Egypt #Jan25

Confusion reigned as to whether the army officers that had joined protesters, ostensibly the target of the operation, managed to escape. This YouTube video by user sawrasilmeya reportedly shows injured and officers being smuggled out in Talaat Harb, 10′ after the shooting started:

@AmrBassiouny: they cleared us out. Pro #jan25 officers escaped safely. Still lots of shooting #tahrir

@AmrBassiouny: Maybe some officers were arrested, but i saw at least 7 out to safety.

Protesters were chased by the security forces in streets around the square. Some managed to regroup temporarily:

@LeilZahra: Most people don't know where to go, it is curfew. Total chaos. But spirit of solidarity is amazing. People still chanting #tahrir

@LeilZahra: Gathering again, people still in the square. Soldiers still shooting heavily. This is a war zone #tahrir #jan25

@AhmedMorsy07: in talaat harb st and the #army chasing us and blocking some exitx #tahrir #egypt #jan25 #april8

This video by Kikhote reportedly corresponds to the Talaat Harb Street sweep:

YouTube user EgyptKingofarab posted a low resolution overhead video reportedly showing a protester being beaten by security forces after being shot.

Photographer David Degner braved the streets and returned with a gripping photoset of the clashes and a chilling sound recording of the heavy gunfire.

The assault continued with heavy gunfire ringing in the square and surrounding streets well after curfew was over, as harried protesters desperately sought shelter:

@ahmadshokr: After 45 minutes, heavy shooting in #tahrir has eased, but sporadic shots still being fired

@lilianwagdy: Pic of #Tahrir now. Almost empty http://twitpic.com/4iitzo

@Rana_Elnahal: Didn't they disperse the protest why the hell are chasing after protesters and shooting fire! #EgyArmy #Tahrir

@degner: Protesters hiding in alleys, two on cell phones, two in the midst of prayer. Gunfire and screams continue. #Tahrir

@ianinegypt: Curfew is technically over but the battle still rages. Cairo once again sounds like a war zone. #Egypt

@lilianwagdy: Made sure that all my friends are safe. Will attempt to get some sleep tomorrow is a big day

Gunfire was still audible as the day dawned, as is evident in this video by Kikhote:

The morning after

The aftermath of the battle found Tahrir Square in disarray, reminiscent of darker days:

Burned out truck in Tahrir. Situation is tense – Photo by Ian Lee on Yfrog

@ianinegypt: Tahrir resembles the revolution. Rocks are everywhere and protesters own the square. #egypt

@liamstack: #tahrir littered w stones. Pool of blood in one corner, men display bullet casings in front of it, occassionally sobbing #egypt #jan25

@mosaaberizing: Barbed wires and barricades have been set in all entrances of the square, no cars allowed in. Haven't seen such thing since #Jan25 days.

@adamakary: Some of the vehicles set ablaze last night were military transport vehicles #tahrir

@Beltrew: Reports from #Tahrir are so confused, we need clear information and then let's target press. We need press coverage of last night. #Egypt

But the toll of the crackdown was more than material, and reports from eyewitnesses were horrifying:

@mosaaberizing: Hearing horrific accounts from last night witnesses. Said the shooting took place for 3 hrs, and army shot directly at them.

@dadatrew: Last night in #Tahrir was terrifying: shooting, stampedes, hysteria, beatings and burning. #Army violence out of all proportion vs civilians

@alaa: baby sis @sana2 was in #tahrir when army cracked down, says some soldiers crying, probably means they got orders to shoot early on #Jan25

@Beltrew: Went to bed fearing #Tahrir would turn nasty, woke up to my sister saying she had fled machine gunfire. It feels like February again. #Jan25

@adamakary: Our sources are quoting eye witnesses saying that two people have been killed from last night's violence in #tahrir

@yasminerashidi: A young man was shot+trampled by army tnk last nite, his body thrown into a garbage dump by army. #egypt #tahrir

@liamstack: doctors: 2 #tahrir protesters dead, 35 injured. #egypt health ministry: 1 dead, 71 injured. lawyers: 42 arrested will get military trial

@pakinamer: Army count for injuries is a far cry from the Health Ministry's official count which said at least one person was killed, and 71 injured!

Evidence of live ammunition having been used was apparently plentiful:

@mosaaberizing: One of the sporadic shots from last night went through the metal bars in the square. http://twitpic.com/4in7xa

@SarahCarr: Picture of live and blank casings used last night by the army against civilians RT @salmasaid http://t.co/qZje09W

@mosaaberizing: Live bullets from last night. #Tahrir http://twitpic.com/4imj9t

Spent ammunition was also evident in Lilian Wagdy's photoset on Flickr of the aftermath of the night's clashes, while the Arabist's Flickr photos displayed wreckage and barricades, in sharp contrast to the joyous scenes of the day previous. Amr Bassiouny also posted photos on Facebook, covering the tail end of the protest, the crackdown and the aftermath.

Anger, divisiveness and hope

Protesters reacted furiously to the bloody crackdown, feeling betrayed by the army, which had never until that point assaulted them so openly and brutally, and angered at the return of riot police, banished from the streets since the early days of the revolution:

@Rana_Elnahal: I cannot believe that riot police are back and beating up protesters. First time since Jan 28. Fuck this. #Tahrir

@mfatta7: I'm a bit puzzled why the generals always attack after midnight when their paymasters in the western hemisphere r awake.

@occupiedcairo: Cowardly #egyarmy waits till 3.30 am to attack peaceful protesters in #tahrir. What is their message?

@curtiskj: Does #Tahrir tonight remind anyone else of #lulu on Feb 16? Attacking late at night, no warning… let's hope Egypt gets a happier ending.

@mosaaberizing: I fear for what happens now. Everyone here feels the army has turned against them and betrayed the revolution. Not good one bit. #Tahrir

@NevineZaki: Asking Egyptians to fault the army is like asking a 10 year old to see his dad as a criminal. Egyptians are still in democracy grade school

@Raafatology: and as I always say, I never trust anyone in uniform except Cheerleaders

To many, it looked that, marred by violence, Tahrir was losing it's spirit on the cusp of rebooting it:

@BloggerSeif: Tweets from #Tahrir are bringing back memories of the time i spent there in #Jan25. :S

@SSirgany: I guess ppl will deliberately avoid getting facts of last night, so they could reach an easy conclusion & have peace of mind.

@Ekramibrahim: In spite of the large numbers at #tahrir yesterday, It was losing it's spirit a big time.

@NadiaE: #jan25 revolutionaries on Twitter i know and trust expressing discomfort and uncertainty with how protests seemed to be going yesterday

@ianniegypt: There is a paranoia in the square. Everyone is suspect. This isn't the Tahrir spirit we've seen in the past. #egypt

@Zeinobia: And here we are split by stupid actions from all parties involved in the tragedy of Tahrir tonight

while others found hope in hardship for the revolution:

@Sandmonkey: This revolution has specific goals, demands & targets, & it shouldn't be swayed every day in a different direction. We should focus! #jan25

@GSquare86: One thing is clear, revolution is just beginning #Jan25 #Egypt

Despite anger at the crackdown, the civic spirit that distinguished the revolution was still in evidence. This video by Amr Bassiouny reportedly shows protesters protecting the National Administrative Government Complex in Tahrir Square, on the morning after the assault:

Speculation and damage control

Speculation about the possibility of an army provocation used to justify the assault was rife:

@steffibied: Gunshots in #Tahrir. Men making molotov cocktails as I walked by pizza hut on Mohammed Mahmoud St. Now home at 3:30 am, shots ringing out

@ianinegypt: A friend walked through Tahrir a half hour ago and claims to have seen protesters making molotov cocktails. #Egypt

@RuwaydaMustafah: People who reported from #Tahrir did not speak of protesters throwing stones, and molotov cocktails being made. Let's be objective.

@Assemism: @RuwaydaMustafah @acarvin I am sorry, but reports circulating here at my side from eyewitnesses ! no molotovs, stones after the CS attacked

@3arabawy: Eyewitness to Al Jazeera Mubasher: Plainclothes policemen believed to be #AmnDawla r conducting arrests in coordination w the army #Tahrir

@ShereefAbbas: Sumthing's very fishy about all of this. Army officers protesting-detained-not beaten, peaceful civ protesters chased by army, beaten by CSF

@Mus_ing: Key question: how confident are we that those in#Tahrir were actually army officers? Why were they avoiding looking directly at the camera?

@NevineZaki: The thing thats puzzling me, how and why did they allow protesters to burn such a massive truck? #Tahrir

The army held a press conference in closed session on the following day, producing a raft of allegations to justify their actions that were vehemently denied by protesters:

@petersbeaumont: Ah the new Egypt. Army tells broadcasters anyone who films press conf will be arrested…. these guys seriously blowing it

@heba_afahmy: 8 protesters wearing millitary uniforms were detained from #Tahrir,army official says investigations will determine whether they r military

@deena_adel: #EgyArmy is now claiming they attacked #tahrir last night because there were NDP thugs causing trouble there. #Egypt

@mosaaberizing: Protesters furious that they're been called thugs & NDP remnants on state media. Propaganda utilized against them just like the old times.

@AmrBassiouny: Lies being spread now on Al Hayat TV, saying that protesters in #Tahrir shot at Military, and empty bullet casings were from protesters.

@beleidy: I don't like the #egyarmy scenario at all, would have respected more if they said we went in to get the officers and things went out of hand

Egyptocracy and Amr Beleidy both livetweeted the press conference, and challenged the logic of the army's allegations:

@beleidy: Army Man saying we caught 3 foreigners, they're using being foreign as an accusation while complaining tourism is not getting back on track

@Egyptocracy: #SCAF dilemma no.1: 8 officers were held by protesters to pressure #EgyArmy, but wait, SCAF not sure if those 8 belong to the army.

@Egyptocracy: #SCAF dilemma no.2: They had to clear #Tahrir because of the curfew, no wait, because of the 8 officers. No curfew. No officers… #EgyArmy

@Egyptocracy: #SCAF dilemma no.3: Officers had no ammunition, but some people had 2 machine guns. Can 2 machine guns produce all those casings? #Tahrir

@Egyptocracy: #SCAF dilemma no.6: They cannot find a good script writer.#Tahrir #Egypt #EgyArmy #Jan25

This post is part of our special coverage Egypt Revolution 2011.