HANOI, Vietnam (AP) — Ten children were among the 56 people killed in a blaze in a Hanoi high-rise, police said Thursday, which some residents desperately tried to escape by jumping out of upper stories, according to witnesses.

Authorities have still not released the cause of the fire, which broke out just before midnight Tuesday and wasn’t extinguished until Wednesday morning in the nine-story apartment building in Vietnam’s capital.

With the fire out, only incense burned Thursday morning outside the building at a makeshift shrine set up by friends and relatives to pay their respects to the dead.

Witnesses told The Associated Press that it appeared that an electrical switchboard caught fire on the ground floor, which was also used for the parking of around 80 motorbikes and bicycles, sending thick smoke billowing through the building.

Nguyen Thi Thu Huyen told the AP that all five members of her family were sleeping on the first floor when they heard someone call out “fire.”

By that time, the smoke was already so dense they could only barely make out flames coming from the floor below them.

She ran out with her 4-year-old son, husband and father-in-law, but her mother-in-law wasn’t able to make it to the staircase in time before it filled with smoke.

Huyen says her husband made it back inside, and then he and her mother-in-law were able to make it down a ladder a neighbor had propped up onto their balcony.

“We’ve lost everything, but it doesn’t matter because the entire family escaped the fire,” she said.

“We survived the tragedy but it breaks my heart that many of my neighbors couldn’t make it.”

As the fire spread, people on higher floors got increasingly desperate and Pham Thu Hang, a pharmacist who lives across the street, said that many began to jump.

“We brought out mattresses and blankets as cushions for people to jump down, but many were panicked and they jumped regardless,” she said. “Some landed on neighbors’ hard roofs. I could hear the thudding sounds. Jumping out would give a better chance to survive than being trapped inside.”

Hanoi police said in a statement Thursday that some entire families were killed in the blaze, and that so far they have only been able to identify 39 of the 56 victims.

Another 37 people were injured, about half of whom were taken to Bach Mai hospital.

Hospital director Dao Xuan Co said that some required immediate operations for head and spinal injuries. Many also suffered broken bones and doctors were checking for internal injuries as well.

“The victims were panicked and jumped off from the tall building, so besides smoke inhalation, they also sustained multiple injuries,” he said.

Prime Minister Pham Minh Chinh and his Cabinet observed a minute of silence at the start of a meeting Thursday in honor of the victims.