NATO chief Jens Stoltenberg will hold talks with alliance ambassadors on Wednesday over the deadly blast in Poland, a spokeswoman said on Tuesday.
"The secretary general will chair an emergency meeting of NATO ambassadors tomorrow to discuss this tragic incident," NATO spokeswoman Oana Lungescu said.
Two people died on Tuesday in explosions caused by a Russian-produced rocket in the Polish village of Przewodow near the Polish-Ukrainian border.
Polish Foreign Ministry later confirmed the rocket fell on the village at 3:40 p.m. on Tuesday, and it has summoned the Russian ambassador to give "immediate detailed explanations."
Russian Defense Ministry denied the media reports by saying, "Polish mass media and officials commit deliberate provocation to escalate the situation with their statement on alleged impact of 'Russian' rockets at Przewodow."
"The wreckage published by Polish mass media from the scene in Przewodow have no relation to Russian firepower," it added.
Poland said an investigation is now ongoing.
Following the reports, Polish President Andrzej Duda has held phone calls with several world leaders regarding the event, including U.S. President Joe Biden, Ukraine President Volodymyr Zelenskyy, UK Prime Minister Rishi Sunak and German Chancellor Olaf Scholz.
UN Secretary-General Antonio Guterres also expressed concern over the missile exploding on Polish territory.
"It is absolutely essential to avoid escalating the war in Ukraine. He sends his condolences to the families of the victims. He hopes that a thorough investigation will be conducted," his spokesperson said.
(With input from agencies)