Bizzare Cloud Phenomenon Before the Quake

Bizzare cloud phenomenon were observed about 30 minutes prior to the May 12 earthquake in Sichuan, China. The clouds were luminous and glowing. Could these clouds precursor to earthquakes?*

The video was recorded in Tianshui, Gansu province ~450km northeast of epicenter, by someone using a cell phone.

The earthquake in Sichuan, measured 7.9 on the Richter scale, killed at least 51 thousand (around 30 thousand more are missing).

*Wikipedia has an entry for earthquake light.