He said the commission had come to the conclusion that the designers of the roof “did not take into account radial and shear deformations that could lead to such shears that the column might simply jump out of its base”.

Mr. Luzhkov the base of the 11th column “was made of fragile steel”. “This could have also played a part in the collapse of the roof,” he added.

According to the Mayor, most theories that appeared in the media earlier, were not confirmed. So, the foundations of the building were “absolutely normal”. “There were no caverns, currents or underground rivers under Transvaal,” he said. The theory that the roof collapsed under the weight of snow, was also rejected. The collapse was not caused by a loud noise either, as “there was no disco party in the building”. The idea that low quality building materials were to blame, also did not work. “The quality of concrete was even better than required for the project,” Mr. Luzhkov said. Reinforcements and welded seams were also of high quality.

The Mayor stressed that a cloud of dust was recorded near the base of the collapsed column moments before the roof caved in. He said this required a serious investigation.

For his part, Nodar Kancheli, who designed the roof of the Transvaal water park, does not agree with the findings of the commission. He blames the tragedy on a terrorist attack. According to him, the Federal Security Service of Russia warned about a possible terrorist act one month prior to the water park incident. But investigators rejected this theory. Moscow Prosecutor Anatoly Zuyev said experts had examined the area and concluded that there were no traces of explosives on the place of the collapse.

The roof of the Transvaal water park in south-western Moscow caved in on February 14, 2004, at 19:15 Moscow time. According to the Emergencies Ministry of Russia, the area of the collapse was more than 5,000 square meters. Twenty eight people died.