A Brooklyn fire was intentionally set and is being investigated as a hate crime — after red swastikas were found spray-painted on a wall, officials said Wednesday.

The FDNY was called to a smoke condition at 374 Myrtle Ave. around 1:20 a.m. on Tuesday, an FDNY spokesman said.

The hateful symbols were discovered in a first-floor hallway after the flames were doused — along with a discarded can of red spray paint, an NYPD spokeswoman said.

There were no injuries in the blaze, she said.

The NYPD’s Hate Crimes Task Force is investigating.

The building has a hair salon on the first floor and apartments upstairs.