BRUSSELS (Reuters) - Spanish and Finnish fighter jets were sent to intercept three Russian planes flying near Estonian air space on Tuesday, the NATO military alliance said in a statement.

The Russian airplanes were identified as two MiG-31 jets and one Antonov AN-26 transport aircraft, NATO said.

“Two Spanish F-18 jets assigned to NATO’s Baltic Air Policing mission scrambled from Estonia’s Amari Air Base,” NATO said. “Finnish jets also scrambled to intercept the aircraft.”

Intercepts of Russian aircraft by NATO have increased in recent years amid heightened tensions between the West and Moscow over Russia’s involvement in the Ukraine crisis.