Law enforcement authorities of the self-proclaimed Luhansk People’s Republic are conducting an investigation into the death of Commander Alexei Mozgovoy, the head of a police battalion in the Eastern Ukraine.

Mozgovoy was killed on Saturday after his car was attacked by gunfire and ran into a land mine, local authorities say.

"According to the preliminary information, the vehicle carrying Mozgovoy was hit by a bomb and then by machine-gun fire," the Lugansk People’s Republic said in a statement.

"There are seven dead in total," deputy Lugansk prosecutor Sergei Gorenko said at a press conference broadcast by Russian media.

Mozgovoi was the leader of the Lugansk's Prizrak ("Ghost”) Brigade militia, one of the most prominent militias in the region.

Defence officials in Kiev have said little about the incident and have taken no formal credit for organizing the attack.

This marks the latest wave of violence in the conflict, which the United Nations estimates has killed over 6,000 people since it began last year.