Russia’s navy practiced firing at targets in the Black Sea off the coast of annexed Crimea using its Bastion coastal missile defense system, Russia’s efense Ministry said on Thursday as Ukraine held joint military drills with the United States.

The exercises in Ukraine involving US and other NATO troops are set to run until October 1. They follow huge war games staged by neighboring Russia and Belarus earlier this month that alarmed the West.

Kyiv’s relations with Moscow plummeted in 2014 after Russia annexed the Crimean peninsula from Ukraine and backed pro-Russian separatists in Ukraine’s Donbass region. The seven-year conflict with separatists has killed more than 13,000 people.

Russia’s Black Sea Fleet practiced detecting and destroying sea targets with its Bastion system, an advanced mobile anti-ship and surface-to-surface defense system, the Defense Ministry said in a statement.

Divisions were shown carrying out strikes with truck-mounted missiles in video footage released by the Defense Ministry. Crews fired from concealed positions and used drones to track a simulated enemy group of ships, it said.

Defense Minister Sergei Shoigu has said the Bastion system can hit sea targets at a distance of 350 km (219 miles) and land targets at a distance of 450 km (281 miles).