A helicopter has been destroyed in a drone attack on a military base in the breakaway region of Transnistria near Ukraine, according to the pro-Russian separatists there. “An old helicopter that was standing on the runway in an inoperable state was burnt,” the Transnistrian security forces told the Russian state news agency TASS on Sunday. There were no reports of casualties. A local broadcaster, which is controlled by the separatists, had previously shown images of the explosion on television. The incident is being investigated, according to officials in Tiraspol. The Transnistria region brok…