The FDNY has determined that a lithium-ion battery caused an apartment fire that killed one person and injured 17 others Friday in Harlem.

The fire took place at a six-story building located on St. Nicholas Place near 149th Street.

Video tweeted out by the NYPD shows firefighters conducting a rope rescue to get those who were living in the building down to safety.

The fire started on the third floor of the building, according to officials.