Russian authorities have detained the owner and the manager of a
nightclub where at least 109 people died in a fire early Saturday.
Officials say the two were taken into custody for violating safety rules at the Lame Horse nightclub in the city of Perm.
A fireworks display meant for indoor use started the fire, which spread quickly after igniting the club's plastic ceiling. Smoke inhalation killed some of the victims; others who died were crushed in a stampede for the exit.
At least 134 people were injured, and many of them are critically ill.
Officials say the club managers repeatedly ignored warnings to comply with safety standards.
Russian President Dmitry Medvedev had harsh words about the incident, saying those responsible "have neither brains, nor conscience."
Moscow called for a national day of mourning to be held Monday.
Russia's emergency, interior and social development ministers went to the scene of the disaster to coordinate relief efforts in Perm, a city of nearly one million people near the Ural Mountains at the eastern edge of European Russia.
Emergency ministry planes will transport some of the injured to hospitals in the Russian capital, 1,200 kilometers from Perm.
Video from inside the club shows the ceiling starting to burn. Club patrons appeared to not immediately realize the facility was on fire, but once they did, they are seen mobbing an exit.
A spokesman for Russia's top investigative unit (Vladimir Markin) was quoted as saying there is no suspicion of a terrorist attack.
Tensions are high following a bombing last week of a Russian express train that killed 26 people. A Chechen rebel group took responsibility for that attack.
A spokesman in Washington (for the U.S. National Security Council) said U.S. officials were "deeply saddened" to learn of the Perm nightclub fire.