4 LA firefighters injured in building blaze

LOS ANGELES (AP) Three Los Angeles firefighters were injured as they tried to rescue a colleague who fell through a roof of a building that was ablaze.

Fire officials say the incident occurred about 3:20 a.m. Thursday at a commercial building. One firefighter fell through a roof that partially collapse and was taken to a hospital in serious condition.

Three other firefighters rushed to the firefighter's aid but also were injured. One was listed in serious condition and the other two were in fair condition.

The blaze was knocked down about an hour after it began.

The cause of the fire is under investigation.