One of the deadliest fires in Minneapolis history roared through a North Side duplex before sunrise Friday, pushing a man who lived there with his seven children to a second-story window ledge yelling, "My kids are burning!" before he jumped to the ground with just one of them.

Five of the children died, overcome by a blaze so intense that an interior staircase collapsed by the time firefighters arrived about 5 a.m. Troy Lewis, the 60-year-old man who leapt from the window, was in satisfactory condition at Hennepin County Medical Center.

Fire Chief John Fruetel said the cause of the fire at 2818 Colfax Av. N.— which housed 15 people in all — is still under investigation. But he said there were no immediate signs to explain what happened, and that the house had no outstanding code violations.

On a day when the children should have been trading Valentine's Day cards with classmates, well-wishers tied pink heart balloons to the porch and friends wept after learning the news.

Neighbor Ayan Ibrahim said that as she watched fire trucks swarm and fire billow from the structure, she "was praying it wasn't the kids, because that house is always full of little kids."

When she learned of their deaths, she added, "I swear, my heart just broke."

The family had been trying to get by since last fall, when the children's mother, Kim Davis, died of heart failure at age 31, leaving her longtime partner, Lewis, to care for them alone. Despite the family's hardships, a downstairs neighbor recalled that she often heard the sounds of little ones laughing.

"They were up there having a lot of fun," said Latonya Garrett, who lived in the duplex's bottom unit.

A close friend of Lewis', Regis Woodson, said that two girls, ages 7 and 8, survived. Shaca and Electra Lewis were in critical condition Friday evening, according to HCMC. Woodson said two boys and three girls died. Two of the children attended Bethune Community School, one in first grade and the other in second.

The fire comes six weeks after a New Year's Day blaze that killed three people in a Cedar-Riverside building, and is the deadliest since an April 2, 2010, fire in apartments above McMahon's Irish Pub on East Lake Street that killed three children, their father, their grandmother and a bartender.

The 102-year-old building on Colfax — a cream-colored duplex with brown trim — is owned by Mission Inn Minnesota Inc., a for-profit company that rehabs single-family and multi-unit properties in north and south Minneapolis that have fallen into disrepair or foreclosure, then signs on low-income families as tenants.

Paul Bertelson, who owns the firm, said the first floor has a furnace, while living areas above are heated with permanent electric baseboard units.

The duplex has smoke and carbon monoxide detectors, properly located near bedrooms and in good working order, Bertelson said. He added that the property passed a city inspection within the past six months, and that the families have been good tenants.

Garrett said Lewis and his family had lived there since about October — with all the children appearing to be under 12.

'Lord, take care of this family'

Just before 5 a.m. Friday, Garrett was asleep with her husband downstairs when her 14-year-old stepson banged on the bedroom door, calling out, "The man upstairs is screaming, and it smells like something is burning."

Still in her nightgown, Garrett ran out the back and saw Lewis sitting on the edge of a second-story window in his boxer shorts, yelling, " 'My kids are burning! The house is on fire!' " she said.

She dialed 911, stumbling over her words in panic. Garrett ordered her four children — three of them toddlers — out of the house.

Soon, while watching the firefighters at work, Garrett's heart sank: She did not see them bringing any children out. "I just started praying, Lord, take care of this family," she said.

Fruetel said the fire began on the second floor then swept through the first and third floors. By the time crews responded, an interior staircase had already burned, and firefighters entered the structure under "very, very, very precarious conditions," the chief said. He confirmed that a space heater was on the second floor, but it was not known whether it had any connection to the fire.

It took fire crews about 2½ hours, working in temperatures teetering around zero, to put out the fire. One firefighter was treated for a minor injury.

"This is a tragic day for the city of Minneapolis," Mayor Betsy Hodges said at the scene shortly after 7:30 a.m.

The Red Cross is offering food and shelter to the people inside the duplex who escaped harm.

Duplex: 'Up to code'

The duplex is licensed for two dwellings and four bedrooms total, according to city property records. Those records show that following an inspection in 2009 the building's owner agreed to fix numerous fire safety hazards, including installing or replacing missing carbon monoxide and smoke detectors throughout the building, and to cap a gas line. Those repairs had to be completed by March 2010.

The exterior and interior of the building were last inspected in July 2013, with numerous violations found, including a smoke detector that needed to be repaired, according to Minneapolis spokesman Matt Laible. The city's records show that the repairs were completed by November 2013, and the property was given a new rental license Feb. 7. Asked whether the duplex had smoke detectors, Fruetel said the building was "up to code."

The number of people living in the upstairs apartment was likely not in violation of the city housing code, which allows for an unlimited number of family members to live in the same registered dwelling.

Even so, overcrowding has become an increasing problem in Minnesota's urban areas, said Chip Halbach, the executive director of the Minnesota Housing Partnership.

"It's being driven by this extremely tough rental market where the vacancy rate is low, rents are going up and renter incomes are declining," he said.

Family's struggle

The death of Kim Davis last fall was a blow to a family that had faced its share of hardship. Lewis and Davis came from Chicago in the last decade and moved frequently in north Minneapolis before landing on Colfax Avenue.

A 2008 child support case shows that the couple were the parents of four children, who would now be between 5 and 9 years old. The children resided with Davis at the time, and Lewis was ordered to pay uninsured medical expenses for them, according to court documents.

Two landlords had evicted them from other North Side properties in recent years for failing to pay rent. One of them, Mahmood Khan, said that after Davis died, Lewis visited Khan at his Friday prayer services.

"He met me at the church and he said come to the funeral because Kimberly had died," said Khan, who recalled Lewis as being protective of the children.

Court documents from 2009 show that Lewis suffered several health problems. He wrote at the time that he had had a stroke and seizures. An accompanying document said he suffers from mild dementia.

By the end of Friday, pink and purple hearts had been planted in the ground and someone had left a teddy bear. Balloons fluttered in the cold wind, one with the face of a red and white puppy.

Woodson had tears in his eyes as he gazed at the hollowed-out home, overcome with the grief his friend would have to bear so soon after losing his partner.

"He was heartbroken," Woodson said. "He could barely make it."

Star Tribune staff writers Tim Harlow, Brandon Stahl and Rochelle Olson contributed to this report. pwalsh@startribune.com • 612-673-4482