MOSCOW (AP) — With the fire alarms silent and staff reportedly nowhere to be seen, a fire at a shopping mall packed with children and their parents on the first weekend of the school recess killed 64 people in eastern Russia.

The fire at the Winter Cherry mall in Kemerovo, a city in Siberia, about 3,000 kilometers (1,900 miles) east of Moscow, was extinguished by Monday morning after burning through the night. Firefighters were still recovering bodies as parts of the buildings were still smoldering. Some of the dead were found inside a cinema.

Sixty-four deaths were confirmed after the firefighters finished combing through the four floors of the mall, Emergency Situations Minister Vladimir Puchkov told a televised briefing. Six of the bodies have not yet been recovered. Puchkov would not immediately say how many of the victims were children.

Ten people have been hospitalized. Health Minister Veronika Skvortsova, who visited the Keremovo hospital where the victims were receiving treatment, said on Russian state television that the patient in the gravest condition is an 11-year-old boy who jumped out of a window from the fourth floor. The boy’s parents and younger brother died in the fire, Skvortsova said.

The Investigative Committee said it has detained four people for questioning, including one of the mall’s tenants, but would not immediately give the cause of the fire, which started on the top floor on Sunday evening. The investigators have launched a probe into possible negligence and violations of the fire safety rules.

Witness testimony indicated that the fire alarm did not go off and that staff did not arrange for the evacuation at the shopping mall, which was was converted from a former confectionery factory in 2013.

Winter Cherry was one of Kemerovo’s most popular entertainment centers for children, with its own indoor skating rink, petting zoo and trampolines. Kemerovo residents said the mall was packed with children and their parents.

The Ekho Mosvky radio station on Monday quoted witnesses who said the fire alarm did not go off and that the mall’s staff did not organize the evacuation.

Anna Zarechneva who was on the top floor where the fire started, watching a movie with her husband and son, said they only found out about the fire when a man ran into the theater shouting.

"We didn’t hear the fire alarm, they even didn’t turn on the light during the show," she said. "That movie could have been the last for us, I’ve only just realized that."

Zarechneva said her husband stayed upstairs trying to help arrange the evacuation because the mall’s security and staff were nowhere to be seen.