MOSCOW, April 5 (RIA Novosti) - Moscow's mayor has pledged to introduce a tough system of control over workers carrying out repair work in residential buildings following Friday's explosion that left three dead.
"There must be the strictest possible system of control over workers' access. Only those with a certificate should be allowed to work," Yury Luzhkov said.
The explosion occurred at around 7:00 p.m. Moscow time (15:00 GMT) on Friday on the 11th floor of a 22-story building on northwest Moscow's Akademika Korolyova street, blowing out walls and destroying several apartments.
The mayor said the new regulations would apply to workers involved in all potentially dangerous activities, including welding.
Although earlier Luzhkov said the accident was caused by unqualified workers carrying out gas welding work, a new version emerged later.
Speaking at a press conference, Luzhkov said Saturday evening that the most likely reason for the blast was careless handling of a propane-butane device by two students.
"These were two friends, students who took interest in making ancient-style weapons like chain mail and helmets. The device with propane-butane they used for soldering exploded. A woman from a neighboring apartment who got under the collapsed slab also died," he said.
Emergencies ministry spokesman Yevgeny Bobylev said earlier 45 people from 20 apartments have been given temporary alternative accommodation pending repair work.
Luzhkov also said: "Summer is approaching, a time when many Muscovites prefer to renovate their apartments. I want to stress that control over renovations will be sharply tightened."
"On Monday I will sign a document on compulsory certification for the right to carry out work with gas welding equipment and hammer drills."
Russian Federal Security Service experts have not discovered traces of an explosive device, a law enforcement officer told RIA Novosti.