Chanry Soeng clutched a cellphone filled with images of her two little boys as she sat sobbing inside her uncle's Bloomington living room Wednesday morning.

It was all she had with her hours after a fire at her South St. Paul home killed her husband, Soeun Sem, 60, and sons Alexander, 5, and Eric, 2, late Tuesday night. Sem and Eric died at the scene, and Alexander died later at Regions Hospital.

Soeng arrived home from work about an hour after the fire began. By then, emergency crews had swarmed the neighborhood and she had to be restrained from running into the house.

"I didn't see my children. I asked police, I want to see my children and they say, 'No,' " Soeng said.

Investigators are still trying to determine what caused the fire at the home in the 300 block of 11th Avenue S., said Mark Erickson, assistant chief of the South Metro Fire Department.

It was the second multiple-fatality house fire this month in the Twin Cities metro area. An Oct. 4 blaze in north Minneapolis killed three young children. Through Oct. 4, the state fire marshal had reported 42 fire deaths in Minnesota this year. There were 41 statewide in 2014.

In South St. Paul, firefighters responded to a call about a garage fire around 9 p.m. Tuesday, Erickson said. When they arrived, they found the basement-level attached garage in flames and fire spreading up the stairs to the first floor of the house.

All three victims were found on the second floor, Erickson said. The fire did not climb to that level, but he said there was smoke damage. Erickson said it was unclear whether the house had smoke detectors.

Fire personnel removed three propane tanks from the garage Wednesday morning, Erickson said, but haven't concluded whether the tanks caused the fire.

Family, friends and co-workers — most of whom grew up in the Cambodian village of Thmor Kol — comforted Soeng on Wednesday. She was pregnant with Alex when she moved to Minnesota around 2008, she said.

Eric followed a few years later. Both, she said, were very smart.

"[Alex would] say, 'Mommy, carrots are good for your eyeballs and your heart, too,' " Soeng said of her son, a kindergartner at Kaposia Elementary School who was fond of Spiderman and SpongeBob cartoons.

Saly Som, Soeng's friend and co-worker, said Eric impressed her by shaking hands and greeting strangers at parties.Sem also had three older children from a previous marriage. Soeng said he did not work because of a disability but enjoyed tending to their backyard garden.

On Wednesday morning, the front of the house appeared unscathed, but the ground level in back — particularly around the garage — was charred and windows were broken.

Records show the house was built in 1930. The family moved there from Inver Grove Heights a few years ago, Soeng said.

Erickson said it was the deadliest fire he could recall in his two decades with the South Metro Fire Department.

"Many of our firefighters have children, some the same age as the victims here," Erickson said.

"And so to put yourself in the shoes of those guys dealing with people that are essentially their children — we treat our patients like it's our children — it's very difficult to deal with."

The state fire marshal is assisting in the investigation.

A Wells Fargo account for donations to the Soeng family was opened Wednesday. Michael Creazzo, a banker at a Bloomington branch, said people who wish to donate can go to any branch and mention the family's name.

By early afternoon Wednesday, stuffed animals, balloons and flowers began to pile up near the Soeng home. Amy Adamson, a former neighbor and babysitter, was among those who stopped by.

"I didn't want to believe they had died," she said. "They were just like my own kids. I loved them to death."

Star Tribune staff writer Liz Sawyer contributed to this report. Stephen Montemayor • 952-746-3282 Paul Walsh • 612-673-4482