MOSCOW (AP) -- Russian rescue workers pumped warm air Sunday into the ruins of an indoor water park, hoping the heat would help some victims survive a day after the roof collapsed, killing at least 25 people and injuring more than 100.
Rescuers shoveled snow from the tangled mass of steel and concrete, some standing atop a large stone that appeared to be part of a mock tropical scene at Transvaal Park on Moscow's southwestern outskirts.
Initial reports said an explosion caused the collapse Saturday night, but Moscow Mayor Yuri Luzhkov and other officials said there was no evidence of a blast. The city has been on edge since a deadly Feb. 6 subway bombing that President Vladimir Putin blamed on Chechen rebels.
The collapse left a hole the size of a football field in the glass-and-concrete roof. On Sunday, cranes lifted heavy chunks of concrete, metal beams and giant buckets of broken building materials.
Rescue workers periodically ordered moments of silence to listen for signs of life.
Investigators said a heavy buildup of snow, the stresses caused by the difference between the indoor and outdoor temperatures, and seepage into the concrete supports may have led to the disaster.
Moscow prosecutor Anatoly Zuyev said faulty construction or maintenance was probably to blame. He said prosecutors were opening a criminal investigation into possible negligence.
They were questioning managers of the park, its architects, engineers and builders, and would also talk to witnesses, Zuyev said. He said pieces of the wreckage would be tested.
The state body in charge of construction, Gosstroi, suspended the licenses of the Turkish company that built the park, Kocak Insaat, and the Russian architectural firm that designed it, the Interfax news agency reported.
Statements about the death toll varied. Moscow Mayor Yuri Luzhkov said Sunday evening that 24 bodies were pulled from the rubble and one person died in a hospital. Earlier, the ITAR-Tass news agency had said the death toll was 28, citing unnamed officials in the city fire department.
Emergency Situations Minister Sergei Shoigu said 17 people were believed missing. That figure was apparently based on belongings left unclaimed at the swimming pool area.
Shoigu said three shifts of search dogs had been sent in Sunday, and that many had cut their paws on broken glass.
Of 111 people injured, 78 remained hospitalized Sunday evening, five of them in critical condition, Luzhkov said. There were 27 children among those hospitalized.
A child's birthday party was being held in the pool area when the roof collapsed, said Moscow police spokesman Kirill Mazurin.
``There was a sudden sound _ a crack _ and my older son said it was like a terrible dream,'' Olga Matveyeva, whose two sons were at the park with their grandmother, told NTV. ``It was as if the roof collapsed in two ... and there was terrible panic as people tried to get out however they could.''
Matveyeva said her sons had escaped in their bathing suits and bare feet and were hospitalized with frostbite.
Altogether, there were about 800 people in the water park complex, and 352 of them were in the pool area when the collapse occurred at 7:15 p.m. Temperatures outside hovered around 5 degrees Fahrenheit.
Roman Yazymin, 29, was sun-tanning in a solarium on the upper floors of the complex when he heard a loud noise and the crash of shattering glass.
``It wasn't an explosion, but the noise of metal collapsing,'' he said and noted that as he walked through the complex to retrieve his clothing ``everything was in blood.''
Rescuers rushed bloodied, moaning people clad in bikinis and swim trunks on stretchers to waiting ambulances, while others clambered out barefoot into the snow.
The collapse left a gaping hole of 5,400 square yards, and torn insulation panels hung off the walls of the cavernous building.
The complex, which opened in 2002, is one of several flashy facilities that have opened in recent years on Moscow's outskirts. It included a large pool, an artificial river and a long water slide.
