BRIDGEPORT — Firefighters responded to a two-alarm fire on the roof of Building 8 of the P.T. Barnum apartments Saturday night, which city fire officials said appeared to be sparked by fireworks.

Firefighters were dispatched to Building 8 around 8:30 p.m. for a reported structure fire. Shortly before 8:50 p.m., officials called for a second alarm to send additional manpower to the scene.

According to initial dispatch reports, the first fire unit on scene reported a working fire on the roof of Building 8. Units indicated that the fire appeared to have been caused by fireworks.

The Bridgeport Fire Department said in a brief statement that fireworks were the “possible cause.”

“Heavy, heavy smoke from the roof,” one arriving unit reported over the radio waves. “Appears to be from fireworks.”

The Battalion Chief on scene said flames were showing as he arrived at Building 8 at 8:35 p.m.

Shortly before 9 p.m., officials on scene reported “heavy fire” was on the roof of Building 8, and that units were transferring to an aerial attack on the flames.

Around 9:20 p.m., fire officials reported the bulk of the flames were extinguished as the aerial attack continued on remaining hotspots. Firefighters were expected to remain on scene for what fire officials said would be “extensive overhaul.”

Bridgeport Transit Authority was alerted of the incident so buses could provide temporary shelter for the occupants of Building 8.

Fire units were recalled around 10:10 p.m. Officials reported the fire was out as crews continued to chase hotspots.

The Bridgeport Fire Department said around 10 p.m. that about 20 fire units responded to the two-alarm fire. The department said it was not immediately clear how many residents would be displaced or how much fire, smoke and water damage had occurred.