Two Russian Sukhoi Su-34 bombers collided over the Sea of Japan on Friday with the pilots ejecting themselves and a search is underway to find them, the Russian defense ministry announced.

The accident took place on Friday morning, when the two planes that belong to the Russian air force in the Far East, crashed during a routine flight.

"On 18 January, at 8:07 (Moscow time), while performing a planned training flight over the Sea of Japan, 35 kilometers from the coast, two Su-34 planes of the Far Eastern Air Defence Forces made contact in the air while manoeuvring," the Russian defense ministry said in a statement.

"An An-12 and two Mi-8 helicopters from the search and rescue forces are searching for the pilots in the area where they ejected," the statement added.

Neither airplane was carrying ammunition, according to the ministry.

Sukhois have a long history of involvement in conflicts, including the Soviet invasion of Afghanistan, Tajikistan's civil war, two Chechen wars and the Gulf War in 1991, where they were employed by Iraq.