St. Petersburg, May 5 : More than 30 regions of Russia have introduced drone flights ban for security concerns, including the two largest cities. Authorities of St. Petersburg, the second largest city in Russia, confirmed on Thursday that its airspace has been closed for drones until May 15. Earlier, an aviation source said that St. Petersburg temporarily banned drone flights from the end of April, Xinhua news agency reported, citing the RIA Novosti news agency. In Leningrad, Governor Alexander Drozdenko said the region has introduced a ban on flying drones. Media reports said the ban was introduced following the explosion of a power line pylon in the Leningrad region on Monday. On Wednesday, a ban on drone flights was introduced in Moscow, the country's capital and largest city, after an attempted drone strike on the Kremlin residence of Russian President Vladimir Putin. More regions in the country are expected to introduce drone flights bans, experts said. /IANS