At least nine people have been injured, three critically, after a building explosion and partial collapse in Chinatown this afternoon. According to the FDNY, the explosion occurred around 12:40 p.m. in a five-story mixed commercial and residential building at 17 Pike Street near East Broadway. Two firefighters were injured along with seven other people; the nine people have been taken to Cornell and Bellevue Hospitals. FDNY added that the fire was under control as of 1:35 p.m.

FDNY said it was not clear yet exactly what caused the collapse, though CBS claims it was an apparent gas explosion.

Update: According to DNAInfo, the explosion was caused by bug bombs. Police sources tell them that one of nearly two dozen pesticide canisters, used to kill roaches and such insects, went off in Piao Liang Ren Sheng Beauty Salon in the rear of the building's first floor, causing the rest to go off in succession. That mass explosion knocked over a load-bearing joist.