LOS ANGELES (CBSLA) – At least three people were injured in an explosion Saturday afternoon that triggered a fire at a single-story commercial building in downtown Los Angeles.

LAFD says it took 140 firefighters a little over an hour to extinguish the blaze, which occurred in a one-story building on a 743 S Kohler Street.  Firefighters were able to prevent fire damage to adjacent adjacent businesses.

The victims — all adult men — were transported to area hospitals. Two are in critical condition with severe burn injuries, the third has unspecified injuries and was transported in fair condition, according to LAFD. Crews will be active on the scene for several hours and the department is asking the public to stay clear of the area until operations are complete.