PERM, Russia — A blaze sparked by onstage fireworks tore through a nightclub ceiling covered in twigs and plastic sheeting early Saturday, killing at least 109 people and critically injuring about 90, witnesses and officials said.

Many victims died in a panicked crush for the single exit as they attempted to escape the flames and thick black smoke, witnesses said.

Hundreds of people had gathered at the Lame Horse nightclub Friday night to celebrate the anniversary of the popular establishment's opening in the industrial city of Perm in the Ural Mountains.

Video recorded by a clubgoer and shown on Russian television showed celebrants dancing before sparks from pyrotechnic fountains on stage ignited the club's ceiling around midnight.

Witness Svetlana Kuvshinova said that the blaze swiftly consumed twigs decorating the ceiling. Russian clubs and restaurants often cover ceiling with plastic insulation and a layer of willow twigs to create a rustic look.

"The fire took seconds to spread," Kuvshinova said. "It was like a dry haystack. There was only one way out. They nearly stampeded me."