Ten civilians have been killed and 13 wounded in rebel shelling of a military checkpoint in eastern Ukraine, officials say.

The rebels shelled the checkpoint near the town of Volnovakha in the Donetsk region while a passenger bus was passing through, according to the Donetsk regional administration which is loyal to the central government in Kiev.

Fighting between Ukrainian government troops and pro-Russian rebels has killed more than 4,700 people since April. Hostilities have intensified in recent days, jeopardising hopes for a peace deal.

The press office for military operations in the east said the rockets appeared to have been fired from a Grad multiple rocket launcher.

Russian news agency Tass cited rebel officials as denying they were responsible for the attack and saying the accusation was "disinformation".

Meanwhile, a group of Ukrainian citizens of Polish descent and their families have been evacuated from eastern Ukraine to Poland, with government aid.

Polish foreign minister Grzegorz Schetyna was present when 178 people, mostly young couples with children, arrived by military planes at the northern airport in Krasnoleka. The evacuation was organised by Poland, with support from Ukraine's authorities.

Poland offered the evacuees six months' stay in vacation centres, language and job courses, free school for children and social security. Local authorities will help them find homes and jobs.