Six people were injured — including one seriously — during an early-morning blaze in a Brooklyn home Monday, officials said.

The flames started inside 3201 Glenwood Ave. near the corner of East 32nd Street in East Flatbush around 6:40 a.m., officials said.

Black smoke quickly engulfed the three-story structure as firefighters battled the blaze, authorities said.

One person suffered serious injuries and was treated at Kings County Hospital, officials said.

Five people suffered minor injuries and were treated at the same hospital, authorities said.

The cause of the fire is still under investigation, officials said.