One person was killed in a blaze that broke out in a rowhouse Tuesday night in the Bloomingdale area of Northwest Washington, authorities said.

The victim was discovered on the first floor of a building in the 1800 block of First Street NW after firefighters had subdued the flames, said Lon Walls, chief spokesman for the D.C. fire department. No information was immediately available about the victim’s age or sex.

The blaze broke out about 7:15 p.m. in a building north of S Street NW that apparently had been converted into apartments.

Firefighters reported intense flames coming from the first floor.

The cause of the fire was unknown, Walls said.

The house, on a block that has been gentrifying rapidly, is south of the intersection of First Street and Rhode Island Avenue NW, and near the area that has been severely affected in recent months by flooding during rainstorms.

“Our prayers are with the family,” Kenyan R. McDuffie (D-Ward 5), who represents the area on the D.C. Council, wrote in a Twitter message.