WEST HOLLYWOOD (KTLA) — At least one person was injured when an explosion rocked an apartment complex in West Hollywood.

A drug lab in one of the apartments is being blamed for the blast.

It happened just after 7:00 p.m. on Friday night (Jan. 25) at a building in the 1200 block of N. Havenhurst Drive.

L.A. County Fire officials say a man was trying to cook marijuana in the apartment.  When he tried to extract THC — the active chemical in marijuana plants — he was handling flammable butane gas that sparked the explosion.

As many as 12 people may be displaced by the blast, which did not spark a fire, but did blow out several walls in the building.  Building & Safety inspectors red-tagged two units.

The man who caused the blast was hurt, and was rushed to an area hospital.

Investigators on Saturday (Jan. 26) were still working to determine if the explosion caused any structural damage to nearby buildings.