Pittsfield crews battled a structure fire on Tuesday.

Firefighters responded to 233-235 First St., and they saw heavy fire and smoke coming from the 235 side of the five-apartment building, Pittsfield Deputy Fire Chief Ron Clement said.

They attacked the fire from the inside, and others searched for any residents. Firefighters do not know if the building was occupied at the time of the fire.

It took around one hour to get the fire under control.

The cause is under investigation.