Part of the roof of a south Minneapolis apartment building has collapsed Thursday morning, hours after smoke and flames began showing.

Members of the Minneapolis Fire Department can be seen just off Portland Avenue along I-35W near I-94, where they’ve been for hours.

Traffic management cameras showed fire crews started battling the flames at the Dundry House on the 1800 block of 5th Avenue South at 11:20 p.m. on Wednesday and continued into Thursday morning.

Fire officials say they found heavy fire on the top floor. They eventually called in a second alarm to get more resources to the site.

Deputy Chief Steffan Swanson says this isn’t the first time crews have been called to this building. They’ve been at that address a number of times over the last few months for fires and other incidents.

Fire crews found several squatters inside, who ran out of the building. Melanie Rucker, Assistant Fire Chief with MFD, said there was evidence that several boards that were supposed to be covering windows had been removed or tampered with.

“When we got here and got the doors open, a lot of squatters or people who shouldn’t be inside were living in there came pouring out. I want to estimate around 15-20 and they just left the scene, they left the area,” said Deputy Chief Staffan Swanson.

Swanson added that those previous fires deteriorated the condition of the building, likely leading to a partial roof collapse early Thursday morning. That prompted the immediate evacuation of firefighters from inside the building as the fire rapidly burned holes in the floor.

Since that evacuation order was made, firefighters have moved to a defensive mode, meaning all crews are outside trying to put the flames out.

Rucker says no injuries have been reported at this time.

It’s too early to tell what started the fire, which will be investigated once the flames are finally out.

Fire crews remain on the scene working to extinguish fire flare-ups and hotspots.

5 EYEWITNESS NEWS will continue to update this article as more information becomes available.