Russian media is quoting the country's defense ministry as saying that troops have started military action in Ukraine.

This comes after President Vladimir Putin announced that Russia will carry out what he called "a special military operation" in Ukraine.

Ukraine's President Volodymyr Zelenskyy said Russia had carried out missile strikes within his country's territory.

Russian media reports quoted the country's defense ministry as saying troops are targeting Ukrainian military infrastructure with high-precision weapons. They say it is not a threat to civilians.

The move comes after Putin made a televised speech, explaining the country is starting a military operation.

Putin did not disclose details. But he said Russia doesn't plan to occupy Ukraine's territory.

Days earlier, Putin unilaterally recognized the separatist regions in eastern Ukraine as independent. He ordered the deployment of Russian troops as what he called peacekeepers.

The Kremlin said on Wednesday that the separatist leaders had asked Russia for military assistance.

In his speech, Putin suggested the action is intended to protect the people who he says have been oppressed by the Ukrainian government.

The Ukrainian President posted a video address on social media. He said Russia had attacked Ukrainian military facilities and border guards with missiles. He said he talked over the phone with US President Joe Biden to discuss the situation.

The Ukrainian border guards service says Russian troops attacked in the northern part of the country, which borders Belarus.

There were reports of explosions in cities across Ukraine on Thursday.