Seven people died and others leaped from windows to safety when a fast-moving fire raced through an apartment building Thursday in Lowell, Mass., authorities said.
"It's a tragic day for the city of Lowell," Mayor Rodney Elliott said.
Officials said four adults and three children died in the fire than consumed the three-story building. Nine people were hospitalized with injuries not considered life threatening.
A police officer on patrol reported the fire just before 4 a.m. ET, while several tenants ran about 100 yards to the nearest fire station to sound the alarm, Fire Chief Edward Pitta said.
The cause and origin of the blaze remain under investigation, State Fire Marshal Stephen Coan said.
Elliott said city prevention officials work hard to ensure the safety of buildings, but added that there are "thousands and thousands" of apartments in the city.
"We do our best to inspect units in this city ... to prevent exactly what has taken place," Elliott said.
As firefighters battled to control the blaze, fear gripped those standing on the streets around the building.
Neighbors said they witnessed people leaping from windows. Chendara Chun, 18, told the Boston Herald she was awakened by what sounded like fireworks, then heard a young girl screaming "Help me, help me." The girl was then tossed from a window to a person on the ground, Chun said.
Felicia Neov told the Boston Globe her mother and several other people stayed in her boyfriend's third-floor apartment Wednesday night.
"They haven't found my mother,'' Neov said. She said her mother's boyfriend told her a roommate smelled smoke and started kicking down doors.
"But my mom and her roommates never made it out of the building,'' Neov told the Globe.
Rotha Proeung told the Herald his 9-year-old son and 11-year-old daughter were in the building with their mother and her boyfriend. He said the boyfriend tried to get them out the door, but the intense fire drove them back so he got them to the window, where they were all rescued by firefighters.
"Very grateful," said Proeung, whose children were treated for smoke inhalation. "They were very frightened."
Authorities said 48 people lived in the building. The mayor said the American Red Cross is accepting donations for the many left homeless.
"The families are going to need clothing, the basic necessities of life," Elliott said. "They have nothing. They've lost everything in the fire."
Contributing: Associated Press