The Russian defense ministry says its troops and pro-Russian forces have seized a settlement on the outskirts of Severodonetsk.

The ministry made the announcement on Sunday. Russian forces are trying to encircle Severodonetsk as part of their efforts to capture the whole of Ukraine's eastern region of Luhansk.

The ministry says Iskander short-range ballistic missiles were fired on a tank repair plant in the eastern region of Kharkiv.

It adds that Kalibr cruise missiles struck military facilities in the eastern region of Dnipropetrovsk, killing more than 50 people including senior officers of the Ukrainian military.

Dnipropetrovsk Governor Valentyn Reznichenko wrote on social media on Sunday that a Russian missile attack caused a massive fire at an oil storage facility, killing two people.

Luhansk Governor Serhiy Haidai posted on social media his interview with a Ukrainian media outlet on Sunday. He said Russia is in control of most of Severodonetsk, and is massing forces in and around the city.

Haidai had earlier said 568 civilians, along with soldiers, remain trapped in the Azot chemical plant in Severodonetsk. He said the number includes 38 children.