Three people, including two boys, were killed after a fire broke out in a Brooklyn building this afternoon, officials said.

The FDNY said firefighters were called to a blaze that broke out in a six-story building on St. Marks Avenue at about 12:28 p.m. in Crown Heights.

Two children, ages 2 and 4, and a 42-year-old man were killed in the blaze after they had been transported to Kings County Hospital in critical condition. The victims were all found in the top floor.

Authorities said the blaze appears to be electrical, WCBS-TV/Channel 2 reported on its Web site.

FDNY Deputy Chief James Campbell said, “We are still investigating the cause. We know it started in the bedroom.”

The victims were not immediately identified.