London, Apr 1 (IANS): Retreating Russian soldiers left 13 dead civilians along a highway leading out of Kiev, with some of the bodies being booby-trapped with mines, according to reports, Daily Mail reported.

Grim eyewitness accounts on Friday suggested Moscow's forces carried out more war crimes in Ukraine, with reports coming out of one city claiming 300 civilians were killed in the last month -- as officials begin the process of recovering the dead.

A separate investigation found that as many as 13 people were killed near Kiev along one stretch of road, including a young couple. Their deaths were captured in a shocking video earlier this month.

The mayor of Irpin, a city recently reclaimed by Ukrainian troops, said this week that up to 300 civilians and 50 'defenders' were killed during Russia's occupation. Up to 50 percent of the city's buildings and critical infrastructure was damaged, he added, Daily Mail reported.

Irpin was home to around 60,000 residents before Russian President Vladimir Putin launched his attack on Ukraine on February 24. Mayor Oleksandr Markushyn said around 3,500 people had stayed in the city, and that officials are still looking for people hidden in their basements.

He pleaded for the city's residents not to return home yet, as it is still under fire from Russian artillery.

Pictures from Irpin Friday showed soldiers carrying body bags down a ruined stretch of road. Now that Ukraine's forces have pushed Russia out of the region, work has been able to begin to collect the dead. Only now is the true scale of the devastation in the city being realised.

According to Olena Halushka -- a member of an anti-corruption group in Ukraine -- some of the bodies were mined by Russian forces before they retreated, creating treacherous booby traps for the recovery workers, Daily Mail reported.