The fire broke out shortly before 3 a.m. on the 1300 block of Adams Avenue in a building where chemicals and computers were stored, said local residents. Fire officials declared the blaze under control at 7:30 a.m.

Residents in the neighborhood said the four-story structure once housed The Anchor Tool & Die Company.

A series of pre-dawn explosions awakened Dave Owens, who lives six-doors away from the warehouse on the 1400 block of Deal Street.

"They sounded like shotguns," said Owens. "I thought it was a couple of idiots having a gunfight."

Wailing sirens drove Owens out of bed. He rushed to the window of his rowhouse. Nearly a dozen fire engines were on the scene in minutes.

"If the blasts didn't wake up my neighbors, the sirens sure did," Owens said. "They were the icing on the cake."

A spokesman for the city Fire Marshal could not confirm the explosions or offer an explanation for the sounds Owens heard.

Investigators have not been able to get into the building to determine the cause of the blaze, the spokesman said.

Flames raced through the warehouse, caused a partial collapse, and sent burning embers flying into the early morning sky.

Walls of fire illuminated the neighborhood, Owens said.

"It was brighter than the street lights," he said. "But we were in the dark. Our power was knocked out. We couldn't watch the news to find out what was happening."

The fire knocked out power for about 1,500 homes, a Peco spokesman said. About 160 homes this morning were still without power late this morning.

Authorities ordered the evacuations of 11 families on Beal Street and the 4300 block of Potter Street. The Thirty people sought shelter and help from the Red Cross at a nearby elementary school, said Red Cross spokeswoman Denise Venuti Free.

Police closed several roadways. Hunting Park Avenue is shut down to traffic between Castor Street and Kensington Avenue and will like remain shutdown for several hours, police said.