Russia-Ukraine updates: Putin suspends key US-Russia nuclear treaty in speech denouncing West

CIA Director Bill Burns traveled to Kyiv to meet with Ukrainian President Volodymyr Zelenskyy on Tuesday, following a meeting with his Russian counterpart in Turkey, according to a U.S. official.

Burns was in the Ukrainian capital during Tuesday's widespread Russian missile strikes.

"He is safe and was safely in the U.S. embassy during the strikes," the official said.

While in Kyiv, the official said, Burns "discussed the U.S. warning he delivered to the head of Russia's SVR not to use nuclear weapons and reinforced the U.S. commitment to provide support to Ukraine in its fight against Russian aggression."

-ABC News' Ben Gittleson

Poland's national police force posted an image on Twitter on Wednesday purportedly showing the site of Tuesday's missile blast, which left two people dead.

The photo showed authorities collecting evidence from a large crater in the ground, alongside debris and a destroyed vehicle.

The Polish Police said in the tweet that its "officers have been securing the area" since the blast happened in the southeastern village of Przewodow, which is close to the border with Ukraine. An investigation into the incident is ongoing, but Polish President Andrzej Duda said Wednesday that the projectile was "probably a Russian-made S-300 missile" and, so far, appeared to be an "unfortunate accident."

Russia on Wednesday noted the "reserved and far more professional reaction" of the United States compared with other countries following Tuesday's missile blast that killed two people in Poland.

"In this case, one should take note of the reserved and far more professional reaction of the American side and the American president," Kremlin spokesman Dmitry Peskov told reporters during a press briefing in Moscow.

Peskov said the U.S. government’s reaction "stood in contrast to the absolutely hysterical reaction of the Polish side and a whole number of other countries."

U.S. President Joe Biden said Tuesday that it's "unlikely" the missile was fired from Russia but that he and other leaders of the G-7 and NATO would support Poland's investigation into what happened. Meanwhile, Polish President Andrzej Duda said Wednesday that the projectile was "probably a Russian-made S-300 missile" but that, so far, it appeared to be an "unfortunate accident."

The missile that killed two people in Poland on Tuesday was apparently an "unfortunate accident," according to Polish President Andrzej Duda.

Duda said Wednesday that the projectile was "probably a Russian-made S-300 missile," according to The Associated Press.

"At the moment, we have no evidence that it was a missile launched by the Russian side," Duda added. "There are many signs that it was an air defense missile that, unfortunately, fell on the territory of Poland."