Two planes carrying bodies from crashed flight MH17 have landed in the Netherlands where a day of mourning for the 298 victims has been declared.
Experts there will begin to identify the dead, most of whom were Dutch.
Pro-Russian rebels have been widely accused of shooting down the Malaysia Airlines plane on 17 July.
UK government sources say intelligence shows rebels deliberately tampered with evidence, moving bodies and placing parts from other planes in the debris.
As fighting continued in eastern Ukraine on Wednesday, officials in Kiev told the BBC that two aircraft, thought to be military jets, had been downed just 35km (20 miles) from the crash site.
The officials had no information on the cause of the crashes, or the fate of the pilots.
US intelligence officials had earlier released evidence to the media that they said showed the separatists’ involvement in bringing down flight MH17.
Rebels have also been accused of exaggerating the number of bodies transported from the crash site to the town of Kharkiv on Tuesday.
They had claimed 282 bodies had been loaded on to a train, but experts said only 200 could be verified.
The two military planes – one Dutch and the other Australian – carrying the first 40 coffins landed at Eindhoven air base to be met by members of the Dutch royal family, Prime Minister Mark Rutte and hundreds of victims’ relatives.
Churches around the Netherlands rang their bells for five minutes before the planes landed.
A fleet of hearses was standing by to convey the bodies to the Korporaal van Oudheusden barracks south of the city of Hilversum for identification.
Rutte said that process could take months.
Earlier, the coffins had been slowly loaded on to the planes by a military guard of honour at Kharkiv airport in eastern Ukraine.
Australian government envoy Angus Houston said the ceremony was intended to give the victims the “respect and dignity they deserve” after a “tragedy of unspeakable proportions”.
In a separate process, the “black box” flight-data recorders from MH17 have arrived in the UK, where they will be examined at the headquarters of the Air Accidents Investigation Branch in Farnborough.
A rebel militiaman told Italian newspaper Corriere della Sera that he had been ordered to the crash site minutes after the MH17 plane had gone down.
He said his commanders had told him: “We’ve just shot down one of the Kiev fascists’ planes.”
The militiaman said: “We thought we were looking for baled-out Ukrainian pilots but instead we found dead civilians.”
Earlier in Washington, officials from the Office of the Director of National Intelligence presented evidence they had gathered on the involvement of the rebels.
“It’s a solid case that it’s an SA-11 [missile] that was fired from eastern Ukraine under conditions the Russians helped create,” said the officials, who requested that their names not be reported.
They said the “most plausible explanation” for the shooting down of the plane was that rebels mistook it for another aircraft.
The evidence they presented included:
• Satellite images of a facility allegedly used to train rebels near the Russian city of Rostov, which were later tweeted by Geoffrey Pyatt, US ambassador to Ukraine
• Other images purportedly showing a surface-to-air missile launcher in the area
• Analysis of voice recordings of pro-Russian rebels apparently admitting bringing the airliner down
• Photos and messages from social-media sites pointing to rebel involvement
Meanwhile, fighting between Ukrainian government forces and rebels around the rebel stronghold of Donetsk has reportedly left 16 people dead.
A statement from overall military commander Igor Strelkov posted on a rebel website said he had withdrawn his fighters from the outskirts of Donetsk.
He said they had pulled back and were prepared to defend their positions.
The fighting in eastern Ukraine erupted in April and is believed to have claimed more than 1,000 lives.