Russia's military defence has taken to the skies for a massive - and unexpected - air force exercise. In a sign of ongoing tensions over Ukraine, 250 aircraft and 12,000 service personnel are involved in the drill, according to its defence ministry.
Independent: Russia begins huge surprise air force drill on same day as NATO start Arctic training
Russian T-90A tanks take part in a military drill at a training ground outside the southern Russian city of Krasnodar on April 14, 2015.
