Off-duty firefighter helps neighbor escape blaze in Gaithersburg townhome

GAITHERSBURG, Md. - An off-duty firefighter helped his neighbor to safety after spotting a fire at their townhome early Friday morning.

Firefighter helps neighbor escape blaze in Gaithersburg townhome (Montgomery County Fire and Rescue)

Firefighter's quick action 

What we know:

The blaze was reported around 5:30 a.m. in the 11900 block of Roan Lane in Gaithersburg. Officials say an Arlington County firefighter, who lives next door, saw the flames, called 911, and banged on his neighbor’s door to alert them.

All occupants escaped unharmed, but two families -- including six children and several pets -- were displaced, according to Montgomery County Fire and Rescue Assistant Chief David Pazos.

The cause of the fire remains under investigation.