(CNN) -- An explosion and fire at a three-story apartment building in Minneapolis Wednesday left at least 14 people hospitalized, six critically, fire officials said. Three residents were believed to be missing and could still be inside.
Freezing weather conspired with heavy flames to hamper efforts to rescue victims and fight the fire, Minneapolis Fire Chief John Fruetel said.
Some horrified residents may have fallen or jumped from the burning building, which also housed a grocery store that served as a gathering place for the area's growing Somali community.
"This is a community that's been through a lot," outgoing Mayor R.T. Rybak said. "People who come to live in this part of our city often have gone through horrendous things. They come here for peace and for safety."
An explosion was reported about 8:15 a.m., and the building was soon engulfed in flames, officials said.
At the time, the temperature at Minneapolis/St. Paul airport, about five miles from fire, was minus 4 degrees F, with a wind chill of minus 18 degrees F, authorities said. Earlier Wednesday morning, wind chills were as low as minus 24 F.
The streets were slick and icy -- flooded and frozen over at the same time. Bright flames two stories high shot up from a frozen gray landscape. Water gushed from windows, forming icicles on the frames. The building and surrounding trees were coated with layers of ice.
"Firefighters in Minneapolis are used to tough weather in the winter," Fruetel said. "Ice and water don't mix well. Certainly we are concerned about the condition of firefighters and are monitoring that. Frostbite can happen very quickly, so we are rotating in personnel as needed."
Most of the injuries were from burns and the "trauma of people that came out through the windows," said Robert Ball, a spokesman for Hennepin County Emergency Medical Services. Officials don't know whether people jumped out, fell or were pushed out by the explosion.
One image from CNN affiliate WCCO showed a badly burned man being lifted out of a window.
Abdi Warsame, a city council member-elect, called on members of the Somali community to come together to aid the wounded and displaced.
"I want the East African community to take leadership and take ownership of this issue, specifically with regards to helping the victims," he said.
Farah Ahmed, a relative of the owner of the grocery store, said the small business was a popular gathering place.
"It was a gathering center," he said. "We started from scratch and we will make it again."
A mosque next door to the building appeared to escape damage.
In a statement, Governor Mark Dayton said: "On behalf of all Minnesotans, I extend my deepest sympathies to the victims of today's awful fire in Minneapolis and to their families and friends. We hope and pray for your swift and complete recoveries. I also want to thank the State Troopers, Minneapolis Police Officers, Firefighters, and other First Responders, who endangered themselves to save the lives of those engulfed by this terrible tragedy."
The three-story building was destroyed, with the roof and the second and third floors collapsing, Fruetel said.
The first floor contained a store; above it were 10 residential units, nine of which "would have been occupied at the time," he said.
Authorities did not know immediately how many people live in those units.
The blaze raged for hours. At first, firefighters tried to enter the building but had to retreat because of the heat, officials said.
The cause of the fire was under investigation.
"This is a Minneapolis tragedy," Rybak said. "This is a Minnesota tragedy. We would like everyone who can help to help."
CNN's Fredricka Whitfield, Kara Devlin, Chuck Johnston, Josh Levs and Carma Hassan contributed to this report.