LOS ANGELES  -  Two firefighters and a bystander were injured Wednesday after a series of explosions blew the manhole covers off the top of an underground electrical vault.

The firefighters were investigating the explosions at a commercial building around 2 p.m. when they were injured, city Fire Department spokesman Ron Myers said.

The cause and extent of their injuries were not immediately known, Myers said. The firefighters were taken to a hospital for treatment. The third victim sustained minor injuries, he said.

The cause of the explosions, which occurred near Los Angeles International Airport, was under investigation.

The explosions ripped into the stucco walls on a corner of the two-story building, which houses the Water and Power Community Credit Union.

(AP)