LOS ANGELES (AP) — Californians have taken refuge under desks and tables in a statewide earthquake survival drill.

The “Great California Shakeout” simulated an earthquake at 10:21 a.m. Thursday, sending participants diving to the floor to practice the “drop, cover and hold” technique.

Organizers say 7.8 million people signed up for the drill, which this year expanded to include some residents of Nevada and Guam.

The drill includes practice responses by fire departments and other agencies. In the San Francisco region, sirens are sounding and all Bay Area Rapid Transit trains were expected to stop for one minute.

THIS IS A BREAKING NEWS UPDATE. Check back soon for further information. AP’s earlier story is below.

LOS ANGELES (AP) — California is set to star in its own earthquake disaster drill.

Now in its third year, scores of people on Thursday will dive under their desks or tables to practice the “drop, cover and hold” technique for surviving a major quake.

Some hospitals and other first responders will stage more elaborate mass casualty exercises complete with search-and-rescue and people posing as faux quake victims.

Some 7.8 million people have signed up to participate in the statewide preparedness drill.

BART says it will stop all trains for one minute.