Russian missiles crossed into Nato member Poland, killing two people, a senior US intelligence official said on Tuesday.

Polish government spokesman Piotr Mueller said top leaders were holding an emergency meeting due to a “crisis situation.”

Considering Poland’s status as an EU and NATO member the strikes would represent a major escalation of the war in Ukraine. 

Russia said no strikes near the Ukrainian/Polish border had been carried out by Russian weapons.

A US Pentagon spokesman said he had “no information to corroborate press reports” but was “taking them seriously and looking into them”.

A UK Foreign Office spokesman said: “We are investigating these reports and liaising closely with allies”.

According to Ukrainian President Volodymyr Zelenskyy, Russia fired at least 85 missiles, most of them aimed at the country’s power facilities, and blacked out many cities.

Neighboring Moldova was also affected, reporting massive power outages after the strikes knocked out a key power line that supplies the small nation.

“We’re working, will restore everything. We will survive everything,” the Zelenskyy vowed.