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By David Bailey
MINNEAPOLIS, Jan 1 (Reuters) - Thirteen people were injured, six of them critically, in an explosion and fire at a Minneapolis apartment building early on Wednesday in frigid temperatures, officials said.
The blast and blaze, which engulfed several apartments and a grocery store, started about 8 a.m. CST (1400 GMT), they said.
Huge flames shot from windows and clouds of billowing smoke enveloped the building as firefighters battled the early New Year's Day blaze in sub-zero temperatures.
"When crews initially arrived on scene, they reported flames shooting as far as 20 feet out of the windows of the second and third floors," Minneapolis Fire Chief John Fruetel told reporters at the scene.
Firefighters climbed an aerial ladder with hoses to douse the fire, and the water quickly formed icicles and a shell of ice encased the building.
Thirteen people were injured and rushed to local hospitals, Fruetel said. Six of those injured were in critical condition, he said.
Residents of the building suffered burns and injuries due to falling or jumping out of windows, Robert Ball of Hennepin County Emergency Medical Services told KARE, a local television station.
The cause of the fire was under investigation, Fruetel said.
"It will certainly take us some time to determine the cause and origin of the fire," he said.
The three-story building is located in an ethnic community of predominantly Somali immigrants, near the campus of the University of Minnesota.
The store also served as a mosque for local residents, said Abdi Warsame, a newly elected City Council member who represents the neighborhood.
"This is a tragic event," he said.
(Additional reporting by Ellen Wulfhorst; Editing by Barbara Goldberg and Andrea Ricci)