KIEV (AFP) - Ukraine's military clashed with pro-Kremlin rebels in two eastern towns overnight, the interior and defence ministries said Thursday.

Ukrainian soldiers retook control of the town hall in the southeastern port city of Mariupol and repelled an attack on an army base in the eastern town of Artemivsk, the ministries said.

Separatist sources confirmed the loss of the town hall in Mariupol, a city with a population of nearly 500,000. The city was the scene of a rebel attack on troops last week that left three militants dead. The separatists had held the town hall since April 13.

"The town hall is liberated and can function normally," Interior Minister Arsen Avakov said on his Facebook page.

In Artemivsk, just north of the rebel-held hub of Donetsk, the defence ministry said in a statement that nearly 100 separatists "opened fire with automatic weapons, machine guns and used grenades" in the attack on the military base.

It said a soldier was wounded, but not critically.

"The attackers were repelled and suffered significant losses," acting President Oleksandr Turchynov said in his own statement.

The interior ministry confirmed the rebel assault and claimed it was led "by a Russian soldier".

There was no immediate confirmation by non-government sources of the incident in Artemivsk.

On Wednesday, the Ukrainian government announced it had re-taken Svyatogorsk, a small eastern village of 5,000 inhabitants - but puzzled locals told AFP there had never been any rebels there.

Kiev accuses Moscow of being behind the insurgency roiling east Ukraine. Russian President Vladimir Putin denies that, though last week dropped a similar denial over the use of Russian forces in Crimea, which Russia annexed in March.

Moscow has said it could strike back if it saw its interests in Ukraine attacked, warning of similar action as in 2008, when it invaded Georgia with tanks.

Russia has an estimated 40,000 troops massed on Ukraine's eastern border.