Ukraine has said that two of its fighter planes have been shot down by missiles fired from within Russian territory, in the latest violence in eastern Ukraine.

"According to preliminary information, the rockets were launched from Russian territory," Kiev's defence council said in a statement on Wednesday. Neither Russia nor the rebels commented on the accusation.

The planes came down close to the village of Dmytrivka, about 45km southeast of where a Malaysian Airlines jet crashed after being hit by a missile last week.

The council added that the Su-25 jets were flying at an altitude of 5,200 metres and were providing ground support for government troops. The pilots from both jets managed to eject, it said.

Pro-Russian rebels have insisted on several occasions that they were not equipped with weapons capable of hitting targets above an altitude of 2,500 metres.

However, a spokesman for the self-proclaimed Donetsk People's Republic told AFP its fighters had shot down the two aircraft.

In a video posted on YouTube, rebels showed the crash site of one of the jets.

Mourning in the Netherlands

The downing of the government jets comes just six days after the MH17 crashed near the Russian border, after apparently being hit by a missile, killing all 298 people on board.

Pro-Russian rebels battling government troops in the east had previously taken out a number of Ukrainian military aircraft.

Kiev alleged last week that an air force transport plane was shot down from across the Russian frontier while another Su-25 jet was destroyed by a Russian plane.

The rebels have denied that they attacked flight MH17 as it flew at some 10,000 metres, accusing the Ukrainian military of being responsible for hitting the jet.

The latest incident came after a ceasefire was declared by both sides in the immediate vicinity of the Boeing 777 crash site, where Malaysian experts and international monitors were examining the airliner's wreckage on Wednesday.

Earlier, the first 40 bodies recovered from MH17 were flown out of the government-held city of Kharkiv and where taken to Eindhoven in the Netherlands, where an arrival ceremony was held for the dead victims.

Investigators hoped two flight recorders, which have been recovered from the crash site and sent to Britain for analysis, would help to shed light on the disaster that killed all 298 on board.

Late on Wednesday, investigators from the Dutch Safety Board said that the date from the cockpit voice recorder was intact and had not been tampered with.

Evidence gathered by US intelligence officials suggests pro-Russian separatists launched the SA-11 surface-to-air missile that blew up the Malaysia Airlines flight on Thursday, but it remains unclear "who pulled the trigger" and why.