A woman was killed and at least two firefighters were injured this morning in an Allston fire that sent nine other residents to the hospital, a fire official said.

One firefighter fell through a second-story floor while another fell down the stairs, Boston Fire spokesman Steve MacDonald said. A total of six firefighters were treated and released from local hospitals.

The fire, which started about 6:30 a.m. on Linden Street, fully engulfed the upper floors. One resident jumped from the upper floors while three others were taken down ladders. An BFD aerial tower was unable to reach the upper floors because of power lines, MacDonald said.

“It got so bad that the chief ordered everyone out of the building,” MacDonald said. “One resident told us someone was missing. We could not make entry. We knew there was a good possibility we would find someone inside.”

Firefighters later found a woman’s body in the attic. Her identity has not been released.

As many as 19 people lived in the house, occupying the basement, two main floors and attic, the fire department reported said. At least six were Boston University students. BU spokesman Colin Riley said he it was unknown whether the dead woman was a BU student.

Eunhee Park, who owns the house across the street, said there was a “loud” party going on well into the early hours this morning.

“Every weekend,” she said, “so loud.”

Park said she was awakened again just after 6:30 by arriving fire engines and saw the second floor engulfed in smoke and a man and woman on a thin sliver of roof outside the front second floor windows.

“They looked scared. They were yelling ‘Help! Help!’ They were just waiting for someone to help them.”

Park’s daughter, Seon Park, said partygoers were milling up and down Linden Street all night before the fire struck.

“As usual, it was loud,” she said. “People were having fun on the street.”

Arson investigators went through the burned building today with a dog sniffing for signs of accelerants but there was no immediate word about the cause of the fire.

The Linden Street property is listed by the city as a two-family with nine bedrooms and two baths.

It is almost directly across the street from a former apartment house where in January 2012 a BU student was critically injured leaping from a window to escape flames, MacDonald noted.

All that remains of that property is a stone foundation surrounded by fence.