A Ukrainian military base about 15 kilometers (9 miles) from the border with Poland was targeted in a Russian missile attack early Tuesday morning, according to information from Maksym Kozytsky, the head of the Lviv regional military administration.

Kozytsky gave no further details in a late-night Telegram post, saying only that further information would be released in the morning.  

A series of explosions were heard in central Lviv around 12:45 a.m. local time (5:45 p.m. ET), shortly after air raid sirens had sounded in the city. A member of CNN’s team in the city saw air defenses lighting up to the northwest — in the direction of the Yavoriv military facility about 40 kilometers away.

In his first Telegram statement shortly after the all-clear sounded at 1:15 a.m. local time (6:15 p.m. ET), Kozytsky said only that air defense systems had responded to the attack. Lviv Mayor Andriy Sadovyi, in a post on his Facebook page, said he could not confirm any information about possible missile strikes in Lviv itself. 

Yavoriv has been targeted at least three times since the start of the war. In the first attack on March 13, more than 30 people were killed. 

Sites in Lviv have also been hit in Russian missiles strikes, including an aircraft parts plant, a fuel depot and several electrical substations.