At least 53 people were killed by a fire in a shopping mall in the Siberian city of Kemerovo, Russia's Emergency Situations Ministry said on Monday.
The fire, one of the deadliest in Russia since the end of the Soviet Union, swept through the upper floors of the mall where a cinema complex and children's play area were located.
Russian emergency services said the fire, which started on Sunday afternoon, has been extinguished but that rescuers are struggling to reach the upper floors because the roof of the building had collapsed.
More than a dozen people were still unaccounted for.
People posted appeals on social media seeking news of their relatives or friends, and authorities set up a centre in a school near the mall to deal with inquiries from people seeking missing family members.
Video footage from inside the mall after the fire broke out showed a group of people in a smoke-filled staircase trying to smash a fire exit door, which was jammed.
Russian state investigators said four people had been detained over the fire, including the owners and leasers of outlets inside the shopping mall.
The Investigative Committee, which handles major crimes, said it was trying to bring in the mall's principal owner for questioning. —Reuters