Three people were killed early this morning in a fire that broke out about 12:30 a.m. in a two-story frame house on 58th Street in far Northeast Washington, authorities reported.

The blaze at 511 58th St. NE also injured three men, and two of them were reported early today in extremely critical condition at the Medstar unit at the Washington Hospital Center.

The cause of the fire was not known, and was reported under investigation this morning.

"It looked like the roof was burning," said Charlene Palmer, who lives across the street from the scene of the fire.

Palmer said she could see no flame, but watched smoke pour from the roof of the 74-year-old dwelling, and saw at least one of the occupants of the house being brought out on a stretcher.

The three persons who died could not be immediately identified. Fire and rescue officials said they were pronounced dead at the scene, a few blocks from the boundary between the District of Columbia and Prince George's County.

The two persons taken to the Medstar unit were described as adult males. No other information about either was available. The third injured person, also described only as an adult male, was taken early this morning by fire department ambulance to D.C. General.

Fire officials said the blaze was reported by people living next door, who noticed flames leaping from a second-floor window.

About 40 firefighters were sent to the scene, and brought the blaze under control in about a half hour, fire officials said. They said it was confined to the second floor of the house.

No estimate of damage to the house was available.

The death toll was believed to be the highest in a fire in the District since March 23 when a 52-year-old man and five children were fatally injured in a blaze at a foster home in Southeast Washington.