Around two hours ago, an earthquake registering 7.8 on the Richter scale struck in southwestern China's Sichuan province, centered in Wenchuan county, and with tremors felt as far away as Beijing and Hong Kong.

Update, Tuesday 9am: QQ has been aggregating video shot by its users from many of the affected areas; many of these videos can be seen here. The video below comes from user Gary, taken in an unspecified location:

The earthquake was reportedly felt in Beijing, Tianjin, Chongqing, parts of Hebei, Shanxi, Shaanxi, Sichuan, Gansu, Henan, Ningxia and Jiangsu.

See below for updates by region.

From Chinese video-sharing website Tudou, user danta1990's footage taken in the Sichuan capital Chengdu:

Danwei has already compiled a number of updates from various sources, as has Shanghaiist, with information on user-shot video from Sichuan Chinese video portal websites were quick to get up on their front pages.

This clip on 56.com comes from user Little Fish in Wenchuan, Sichuan:And this from video sharing website Youku.com comes from user xiaoyu82528, showing the effect of the earthquake as felt as far away as Beijing:Twitter seems to be a top source of breaking details for the moment; Many are writing of difficulties connecting to those at the center of the quake zone over telephone, but the internet seems to still be functioning. Beijing-based tech guru Kaiser Kuo writes that the government Seismological Bureau website is currently inaccessible, presumably from high levels of traffic.

Users inwalkedbud and Lyrrael have been posting updates in English, reporting what they can. River Crab Goes Ashore has been collecting live updates on Chinese microblogging service provider Fanfou.

Inwalkedbud writes from Chengdu, quite near the center of the earthquake: “Doesn't seem to be much damage to buildings, but people are shaken up. Electricity/water/gas seems to be working still.”

Other areas have not been as fortunate; Chinese Twitter user Raine, based in Hubei, writes of possible destruction there:

同事刚电话回家，湖北的荆州、沙市的房子倒了一片，有灾情。

Also via Danwei is a note to keep following Summize.com, one Twitter search engine which supports Chinese characters, for steady updates; updates found via Summize and other places will be added here as they are found. Photos can be seen on Flickr via searches for ‘earthquake’ in English and Chinese and on Yupoo.com.

Anyone with more information regarding other areas around China that have been affected is invited to gives us a heads-up in the comments.

Microblog updates by region:
Sichuan
Photos of the devastation in Jiangyan, Jiangsu provinceDujiangyu, one of the hardest-hit places known so far. Several portray dead bodies.

Monday 21:52 http://jiwai.de/IQ%E5%B0%8F%E5%AD%90/statuses/8802456

“English”语言的维基百科“List of earthquakes”词条中已经增加了此次四川大地震的内容,此外该语言已经新增了“2008 Sichuan Province earthquake”的词条。中文维基百科尚无相关内容更新。

Monday 22:40 http://jiwai.de/doggienest/statuses/8803411

往成都固定电话打通了

http://fanfou.com/statuses/g2QgIe8OWzM
Monday 22:25 http://ledao.in/blog.php?blog_id=156

汶川是去九寨沟的必经之路，那里山势陡峭，地表植被因过度开采受损，而岷江流经此地，造成水土流失严重，是个容易发生地质灾害的地方，这次惨了。

四川大学要求同学离开宿舍 通知4点余震开始

https://twitter.com/shizhao/statuses/809213970

据说四川地区CDMA，小灵通可以打通

https://twitter.com/niubi/statuses/809205236

chengdu airport closed. flights heading there beijing redirectede to chongqing

https://twitter.com/guiyinzhang/statuses/809162622
Monday 5:30 pm: https://twitter.com/Aether/statuses/809193571

成都互联网通讯有能连上的了。

http://fanfou.com/statuses/l6XlCAxBJCI

绵阳花盆啥的都碎了，饮水机震倒说塌了好多房子，人都到河堤上去了

http://fanfou.com/statuses/aOdJ1I6y1YU

四川阿坝州理县县城1人死亡8人重伤 汶川县发生7.8级地震后，截止12日17时10分，阿坝州政府应急办了解到的情况是：汶川、理县、茂县交通、通讯全面中断，黑水、小金、金川、马尔康、松潘、九寨沟等县均有房屋倒塌、道路中断、山体滑坡、人员伤亡(其中茂县林业电台报告伤亡人员较多，

Beijing
https://twitter.com/flypig/statuses/809127403

中国南北网络断了吗？怎么啥都上不去了？

https://twitter.com/imagethief/statuses/809121832

@goldkorn I could actually see other buildings in Gemdale moving — could see their reflections in the glass moving.

— Kaiser Kuo (@KaiserKuo) May 12, 2008

@Scobleizer Lasted longer than 10 seconds — the swaying of my building anyway went on for 30-40 seconds.

— Kaiser Kuo (@KaiserKuo) May 12, 2008

@goldkorn obviously I can feel it at SOHO New Town.

— Tangos Chan (@Tangos) May 12, 2008

https://twitter.com/niubi/statuses/809132301

I was sitting outside at the coffee shop and had no idea re: quake, except for dog whimpering/jumping.

— Andrew Lih (@fuzheado) May 12, 2008

photo https://twitter.com/flypig/statuses/809135452

Shanghai

breathing normal again. feeling an earthquake on the 31st floor was not fun.

— ana campos (@nocas) May 12, 2008

CREEPY! while i'm typing, there's an aftershock hitting!

— Casper Oppenhuis de Jong – Baerts (@casperodj) May 12, 2008

[地震] 上海浦东，毫无震感

— BroX (@leoshcn) May 12, 2008

Shaanxi

[地震] 汉中市地震局 0916-2626496

— 葡萄 (@yesky12) May 12, 2008

@nober 我也是。。只能和西安那边发短信，电话打不进去。。

— 陳堃 (@tansunit) May 12, 2008

只能和西安那边发短信，电话打不进去。。

Henan
Monday 21:39 http://jiwai.de/jiangyh/statuses/8802154

15时48分，河南省地震局通过手机短信、电视、广播等形式，向群众发布震情提示：“地震台网测定今天14：28四川汶川发生7.8级地震，震感波及我省，不会影响正常生活，请不要恐慌，本局正关…

http://fanfou.com/statuses/O8h2ttRuQJ8

郑州国家电网公司的大楼都疏散到空地了

Jiangxi
http://fanfou.com/statuses/7bjUhAwYzH8

Anhui

[地震] 我在安徽淮南,这里没有地震

— 戴书文 (@daishuwen) May 12, 2008

Guangdong
Monday 21:19 http://fanfou.com/statuses/LhifhcSKPXw

76年的唐山地震马上就被翻出。现在全国最忙碌最紧张最加班加点的部门不是地震局，不是救灾队，是中宣部

Zhejiang

杭州网络正常。公司大部分同事都跑到外面去了。

— Fenng (@Fenng) May 12, 2008

杭州网络正常。公司大部分同事都跑到外面去了。

http://fanfou.com/statuses/k0jIs0Mkmz8

浙江嘉兴、上海间发生5.7级地震 暂无人员伤亡

http://fanfou.com/statuses/nOwacdhRpdA
宁波世贸中心大楼倾斜3度！！！！！！！！！！！！
The World Trade Center in Ningbo has tilted 3 degrees!!!!!!!!

Chongqing

2 school damaged, 4 students dead in Chongqing (from zaobao) http://tinyurl.com/6g5ump

— Tangos Chan (@Tangos) May 12, 2008

https://twitter.com/shizhao/statuses/809211439

重庆2小学倒塌，4学生死亡

Changsha
http://twitter.com/dadi007/statuses/809209238

Guangxi
http://fanfou.com/statuses/8lgMEGMOzUE

Hubei
Wuchang: http://twitter.com/lenvow/statuses/809197185

湖北多地有地震震感 武昌出现手机信号盲区