UPDATE - US says 'looking into' reports of Russian missile strikes in Poland

ADDS NSC TWEET IN GRAFS 8-9, BACKGROUND IN GRAFS 10-12

By Michael Hernandez

WASHINGTON (AA) - The US vowed Tuesday to "defend every inch of NATO territory" after Russian missiles reportedly struck alliance member Poland, killing two people.

Pentagon spokesman Brig. Gen. Pat Ryder could not immediately confirm if the explosions were the result of Russian missile strikes but said the Defense Department was looking to confirm the reports.

"We are aware of the press reporting on this. We have no information at this time to corroborate those reports, but again, we are taking them seriously and looking into them," Ryder told reporters at the Pentagon.

"I don't want to speculate or get into hypotheticals. When it comes to our security commitments, and Article Five, we've been crystal clear that we will defend every inch of NATO territory," he added, referring to NATO's collective defense principle.

The reported attacks that hit Poland's eastern village of Przewodow come as Ukraine faces a wave of missile strikes that have again targeted the war-torn country's energy infrastructure, knocking power out for millions of people. Some Russian strikes hit targets in the western part of the country close to the border with Poland.

Polish Prime Minister Mateusz Morawiecki has convened an urgent high-level meeting to discuss the matter, government spokesman Piotr Muller said shortly after reports of the explosion began.

The White House said it is working with Morawiecki's government "to gather more information" on the explosions, and "will determine what happened and what the appropriate next steps would be."

"We cannot confirm the reports or any of the details at this time," National Security Council spokeswoman Adrienne Watson said on Twitter.

Earlier, The Associated Press quoted an anonymous senior American official as saying Russian missiles crossed into NATO member Poland, killing two people.

Russia's Defense Ministry denied carrying out any attacks near the Ukrainian-Polish border.

"The fragments published in hot pursuit by the Polish media from the scene in the village of Przewoduv have nothing to do with Russian weapons," Russia said.