The downing of the Malaysia Airlines flight MH17 in eastern Ukraine may constitute a war crime, UN human rights chief Navi Pillay said Monday.
Ukraine and the West believe that pro-Russian rebels shot down MH17 using a missile system supplied by Russia, BBC reported.
Russia and the rebels have blamed Ukrainian forces for the plane crash.
Dutch and Australian police are reported to be heading for the site for the second time Monday after clashes between rebels and military broke out Sunday in and around the crash site.
Most of the bodies have been removed and repatriated to the Netherlands.
The Ukrainian army is trying to take control of two main roads, which the government in Kiev believes to be vital supply lines from Russia for rebel forces in Donetsk.
Since Sunday, there has been heavy shelling in the city of Horlivka in eastern Ukraine.
Flight MH17, a Boeing 777, was flying from Amsterdam to Kuala Lumpur when it crashed after being hit by a missile in Ukraine near the Russian border July 17, killing all 298 passengers and crew on board.
This is the second major tragedy for Malaysia Airlines this year after flight MH370 with 239 passengers and crew on board went missing while flying from Kuala Lumpur to Beijing March 8. The flight remains untraced till date despite intense international search efforts.
