At least 15 people were killed and 90 others injured when a glass roof collapsed at a popular water amusement park in Moscow, late Saturday.
The roof fell onto scores of people swimming at an indoor waterpark complex that is popular with children and their families.
Moscow's mayor says at least one child was among those who died when the roof came crashing down. The park was packed with people when the incident occurred.
Officials say they suspect the roof fell due to heavy snow that accumulated over the past few days.
Television showed scenes from inside where concrete beams had fallen onto the park's twisting water slide. Rescue teams pulled many people out from under debris, although most injuries were caused by the shattered glass of the roof.
The park was built relatively recently and police are investigating details of the construction work carried out on the facility.
The park was one of several recreational centers that have been built in recent years, places where Muscovites can seek a respite from the cold and snow of winter.
Initial reports suggested the incident was possibly caused by an explosion, but police say there is no evidence of that.
Moscow's been on edge ever since at least 41 people died in an apparent suicide bombing on the city subway just over a week ago that was blamed on rebels from breakaway Chechnya.