KYIV, April 2 (Reuters) - At least three civilians were killed and six wounded in Russian shelling of Kostiantynivka in eastern Ukraine on Sunday morning, a senior Ukrainian official said.

Kostiantynivka, home to about 70,000 people before the war, is just 20 km (12.5 miles) west of Bakhmut, the epicentre of fighting for at least eight months as Russian forces try to capture the city.

"Russians have carried out massive shelling of the town of Kostiantynivka," Andriy Yermak, head of Ukrainian President Volodymyr Zelenskiy's chief of staff, said on the Telegram messaging app.

A photos published by Yermak showed the partial destruction of buildings and craters from explosions.

Reuters could not independently verify the authenticity of the photos and the number of casualties.

(Reporting by Pavel Polityuk; Editing by Frances Kerry)