Glowing clouds seen before China's earthquake

Bizarre colorful (luminous/glowing) cloud phenomenon in the sky was observed about 30 mins before the May 12, 2008 Sichuan earthquake took place. This was recorded in Tianshui, Gansu province ~450km northeast of epicenter, by someone using a cell phone.
source: http://news.qq.com/a/20080513/004283.htm

See similar cloud formation captured 20 minutes later in a different city, ~200km east of this location: http://www.youtube.com/watch?v=hzVamN...

A map of the locations with sightings of very similar phenomenon.
http://img223.imageshack.us/img223/24...

More photos:
http://shenyun.epochtimes.com/b5/8/5/...

These clouds seemed to be glowing or somewhat luminous and seemed to resemble some characteristics of the Auroras. I guess they were formed by some kind of charged particles released from the powerful seismic events below. Well, I am no expert anyways. See if any scientists are willing to give a full explanation.