Minneapolis firefighters, in what has been a busy holiday week for them, on Friday were called to extinguish a two-alarm blaze at an under-construction duplex in the Corcoran neighborhood.

The fire at the building in the 3500 block of S. 21st Avenue was brought under control about 4:45 p.m. No one was hurt.

Firefighters had cleared the first and second floors around 3 p.m. before encountering a "heavy fire" on the roof. The blaze was deemed a two-alarm fire shortly after as crews evacuated the building. Part of the roof collapsed minutes later.

Around 3:45 p.m., crews re-entered the building to extinguish remaining hot spots.

The cause of the blaze, which came two days after a huge fire at Minneapolis' Drake Hotel that displaced many homeless families, is under investigation.