It's Russia's appalling health and safety standards. Hundreds die in similar fires every year.
" ... Svetlana Kuvshinova, who was in the club when the fire began, said the flames "took seconds to spread".
"It was like a dry haystack. There was only one way out. They nearly stampeded me," the Associated Press quoted her as saying.
Another eyewitness told local TV: "When the merry-making started, when they were warming up, they set off fireworks.
"When I turned back, I saw drops falling off the ceiling and then there was a lot of smoke. Later this huge flame was moving along the ceiling," the unnamed woman said.
A spokesman for the prosecutor-general's main investigative unit told Itar-Tass that it was not a terrorist attack.
"We are talking about a failure to observe fire regulations," he said. .... "
BBC News - Russia nightclub fireworks blast kills scores