(Reuters) -Air raid alerts were declared throughout Ukraine early on Friday, with some areas reporting explosions. Officials said anti-aircraft units were in action in several regions.

Far western regions were initially left out of the warnings but officials later extended them to the entire country.

Ukraine's military said on Telegram that Russian aircraft were in the air and there was a threat of strikes from hypersonic Kinzhal missiles to all regions.

An earlier military statement said some airborne targets had been downed, but gave no details.

The military said central regions were at risk from drone attacks.

Officials in Kyiv said anti-aircraft units were in operation. Explosions were reported in other cities, including in the central city of Kriviy Rih, without details.

(Reporting by Ronald Popeski; Editing by Leslie Adler and Jacqueline Wong)