In what could be a first, Russian air force units have started attacking targets in western Ukraine, according to information coming from the Ukrainian side.

At least six long-range Tupolev Tu-95 bombers had used air-to-surface missiles against targets in Lutsk and Ivano-Frankivsk, Ukraine said.

According to media reports on Saturday, a factory repairing fighter jet engines was hit in Lutsk, and the central Ukrainian city of Dnipro was also attacked.

The Ukrainian air force said it had flown about 10 missions with MiG-29 and Su-27 fighter jets, including to attack enemy aircraft.

None of the information could be independently verified.

According to Ukrainian authorities, an ammunition depot and a fuel depot were hit during a Russian attack on a military airfield in Vasylkiv south of Kyiv overnight. The airfield was completely destroyed.

According to the Ukrainian authorities, the northern city of Chernihiv, which has been under attack for days, is largely without electricity, water, heating and gas.