CNN: Russian airborne troops take control of airport located about 25 miles away from the center of Kyiv

Russian airborne troops have taken control of the Antonov Airport, which is about 25 miles away from the center of Kyiv, Ukraine, according to CNN's Matthew Chance.

CNN reporters on the ground have witnessed rockets appearing to be launched from Russia to Ukraine, military vehicles headed to the country and families crowded in a subway station for shelter.

The Ukrainian Interior Ministry confirmed that one Russian helicopter and three other unknown helicopters were downed in the Kyiv region.

After a speech from Russian President Vladimir Putin announcing a military operation in the Donbas region of eastern Ukraine, Russia launched a large-scale invasion on Ukraine at about 5 a.m. local time.

"It was very tough this morning," Lviv Deputy Mayor Andriy Moskalenko told CNN on Thursday morning. "This morning, we had sirens and it was a sign for people to move to underground shelters ... the explosions were far away from the city."