Russia claimed that a Tuesday explosion in Poland was brought on by a Ukrainian air defense missile and that Russian strikes in Ukraine were no closer to the Polish border than 35 kilometers (22 miles).

Moscow summoned the Polish chargé d’affaires and said it had nothing to do with the explosion, which claimed two lives.

On Wednesday, the Kremlin claimed that several Western nations, particularly Poland, had reacted “hysterically,” but claimed that the United States and President Joe Biden had exhibited calm.

“The photos published in the evening of Nov. 15 in Poland of the wreckage found in the village of Przewodow are unequivocally identified by Russian defense industry specialists as elements of an anti-aircraft guided missile of the S-300 air defense system of the Ukrainian air force,” the Russian defense ministry said.

It was not possible to independently verify the images or the identification.

Kremlin spokesman Dmitry Peskov said a number of countries had made “baseless statements” about Russia’s involvement “without having any idea of what had happened”.

“We have witnessed another hysterical, frenzied Russophobic reaction, which was not based on any real data,” Peskov told reporters.

But Peskov said Biden had shown “restraint” in his response. In his first comments, Biden said early assessments showed it was unlikely the missile had been fired from Russia.

“Once again, I want to invite you to pay attention to the rather restrained reaction of the Americans, which contrasted with the absolutely hysterical reaction of the Polish side and a number of other countries,” Peskov said.

A NATO source said Biden had informed Group of Seven and NATO partners that the blast in Poland, a NATO member, had been caused by a Ukrainian air defence missile.

Asked whether officials from Russia, the United States and NATO and had used an emergency hotline designed to prevent a nuclear escalation, Peskov said he was not aware of any calls having taken place.

Poland’s president said earlier that Warsaw had no concrete evidence to determine who fired the missile, which struck a grain facility some 6 km (4 miles) inside the border with Ukraine.

Russia’s defence ministry also said it had not targeted Kyiv during Tuesday’s widespread strikes. Reuters journalists in the city reported missile strikes, including on residential buildings, and power outages across the city in some of the heaviest attacks in the nine-month conflict.

In a statement after the Polish envoy’s visit, Foreign Ministry spokeswoman Maria Zakharova complained that “despite the fact that it was night-time and the absence at that time of any reliable information about what happened, Warsaw considered it necessary to summon the Russian ambassador to the Polish Foreign Ministry and make a political show out of this”.