Russia said on Wednesday it had hit the command headquarters of the Ukrainian army’s southern group, which is based in the port of Odesa, in a missile operation that Kiev said killed three people.

“The headquarters of the operational command of the southern group of the Armed Forces of Ukraine was hit by operational and tactical aviation, missile forces and artillery,” the Russian Defense Ministry said.

The Russian military did not elaborate on the attack, but said that Russian forces improve their positions along the entire front line.

The Ukrainian command said residential buildings, not military infrastructure, were damaged in Odesa in a night attack, while the southern military command said administrative and residential buildings, medical and educational institutions were hit.

Odessa it is a frequent target of Russian forces in the more than two-year war, with many attacks targeting the city’s port facilities.