At least 5 injured in explosion, fire at Bronx building, FDNY says

An explosion at a Bronx building left at least five people injured amid a multi-alarm fire, firefighters said.

The FDNY said it received a call just before 12:30 p.m. Wednesday about an explosion and fire at 374 East 209th Street in the Norwood section.

It quickly escalated to a five-alarm fire engulfing the second and third floors. 

Fire officials said at two of the five people were critically hurt. 

Police sources told CBS News New York a lithium-ion battery is suspected to have been involved, possibly from an e-bike, although an official determination will be made later. 

Firefighters expect smoke and traffic delays in the area.

Crews are urging people nearby to avoid smoke and close windows as they continue to put the flames out.

FDNY social media video shows flames pouring out of the building as they battled the blaze.