A Russian air strike on a large Ukrainian military facility at Yavoriv near the border with NATO member Poland on Sunday killed 35 people and wounded 134.
Britain said the incident, just 15 miles (25 km) from the Polish border, marked a “significant escalation” of the conflict.
U.S. President Joe Biden has said NATO would defend every inch of its territory if Russia’s invasion of Ukraine spills over into member states of the Western defence alliance.
Ukraine said foreign military instructors have previously worked at the Yavoriv International Center for Peacekeeping and Security, but a NATO official said there were no personnel from the alliance there.
It was not immediately clear whether any non-NATO states might have representatives there.
Regional governor Maksym Kozytskyy said Russian planes fired around 30 rockets at the facility, adding that some were intercepted before they hit. At least 35 people were killed and 134 wounded, he said.
The 360 sq km (140 sq mile) facility is one Ukraine’s biggest and the largest in the western part of the country.
The Kremlin did not immediately reply to a request for comment on the reported missile strike so close to the border with NATO, and a short video briefing by Russia’s defence ministry spokesman on Sunday made no mention of such an attack.
Nineteen ambulances with sirens on were seen by Reuters driving from the direction of the Yavoriv facility after the reported strike and black smoke rose from the area.
“Russia has attacked the International Center for Peacekeeping & Security near Lviv. Foreign instructors work here. Information about the victims is being clarified,” Ukrainian Defence Minister Oleksii Reznikov said in an online post.
‘VIOLENT AND INHUMAN’
A Ukrainian defence ministry representative told Reuters the ministry was still trying to establish if any foreign instructors were at the centre at the time of the attack.
Ukraine, whose aspirations to join NATO are a major irritant to Russian President Vladimir Putin, held most of its drills with countries in the Western defence alliance at the base before the invasion.
The last major exercises were in September.
In the weeks before Russia invaded on Feb. 24, the Ukrainian military trained there, but according to Ukrainian media, all foreign instructors left the training ground in mid-February, while leaving all the equipment.
Russia’s invasion of Ukraine, launched by Putin on Feb. 24, has sent more than 2.5 million people fleeing across borders and trapped hundreds of thousands in besieged cities.
“It is terrifying how violent and inhuman it is,” Olga, a refugee from Kyiv, told Reuters after crossing the border into Romania.
Ukraine reported renewed air strikes on an airport in the west, heavy shelling on Chernihiv northeast of the capital Kyiv and attacks on the southern town of Mykolayiv, where officials said nine people had been killed.
