内容摘要：A Mi-24 helicopter crashed over the Black Sea near the western coast of Crimea on Wednesday, said Ru

A Mi-24 helicopter crashed over the Black Sea near the western coast of Crimea on Wednesday, said Russia's Ministry of Defense.

The helicopter crashed at around 6 a.m. Moscow time (0300 GMT) while performing a scheduled flight, the ministry said.

The preliminary cause of the crash was technical failure, and the search and rescue services are at the scene, it added.