Two military aircraft carrying the first bodies of victims of the Malaysia Airlines crash left the embattled plains of eastern Ukraine Wednesday, and pro-Russian rebels shot down two Ukrainian fighter jets as fighting flared in the region.
British investigators began work on a pair of "black boxes" to retrieve data on the flight's last minutes, while Dutch officials said they have taken charge of the stalled investigation of the airline disaster and pleaded for unhindered access to the wreckage.
The Dutch government declared a day of national mourning as the country prepared for the arrival of the first bodies in the afternoon. The crash on Thursday killed all 298 people — most of them Dutch citizens — aboard Malaysia Airlines Flight 17.
The two military transport planes, one Dutch and one Australian, departed Ukraine at midday, heading for Eindhoven air base where the flights will be met by Dutch King Willem-Alexander, Queen Maxima, Prime Minister Mark Rutte and hundreds of relatives.
Ukraine and western nations are pressing the pro-Russian rebels who control the crash site to allow an unfettered an investigation, something Russian President Vladimir Putin said he would use his influence to achieve. Though confident that a missile brought down the passenger jet, U.S. officials say Russia's role remains unclear.
Ukraine's defense ministry said two fighter planes were shot down about 30 kilometers south of the site of the Malaysia Airlines wreckage.
While the insurgents deny having missiles capable of hitting a jetliner at cruising altitude, rebel leader Alexander Borodai has said that separatist fighters do have Strela-10M ground-to-air missiles which are capable hitting target up to an altitude of 3,500 meters (11,500 feet).
Rebel leader Pavel Gubarev wrote on his Facebook page that his men retreated Wednesday from the villages of Chervona Zorya and Kozhevnya, on the Russian border about 45 kilometers (30 miles) from the scene of the crash. Gubarev said 30 rebels had been injured.
Britain's Air Accidents Investigation Branch said Wednesday that Dutch authorities had delivered the plane's voice and data recorders to the agency's base at Farnborough, southern England, where information will be downloaded. Experts will also check for signs of tampering.
The Dutch Safety Board, which is leading an international team of 24 investigators, and said unhindered access to the crash site is critical.
Tjibbe Joustra of the Dutch Safety Board told the AP in a telephone interview that around 25 investigators already are in Kiev analyzing information including photos, satellite images and radar information, but have not yet gained access to the crash site.
"We haven't yet gotten guarantees about security for our way of working. If we go we have to be able to move freely," he said. "We hope to be able to get to the site soon."
For one grieving mother in the Netherlands, the return of the bodies marked a new stage of mourning and brought to an end the pain of seeing television images of victims lying in the undulating fields or in body bags being loaded into a train.
"If I have to wait five months for identification, I can do it," said Silene Fredriksz-Hoogzand, whose son, Bryce, and his girlfriend Daisy Oehlers died in the crash. "Waiting while the bodies were in the field and in the train was a nightmare."
Dutch government spokesman Lodewijk Hekking said about 60 coffins were expected, but the number wasn't immediately confirmed.
There was confusion as well about how many of the 282 corpses which the rebels said they have found were on the train which arrived in Kharkiv, a government-controlled city, on Tuesday.
Jan Tuinder, the Dutch official in charge of the international team dealing with the dead, said that at least 200 bodies were aboard the train and that more remains could be found once the body bags are examined fully.
The European Union on Tuesday imposed sanctions against more Russian individuals but refrained from targeting entire sectors of the Russian economy while waiting for clearer evidence of Moscow's role in the disaster.
U.S. officials say the plane was probably shot down by a missile, most likely by accident.
Senior U.S. intelligence officials said Tuesday that Russia was responsible for "creating the conditions" that led crash, but they offered no evidence of direct Russian government involvement.
The officials, who briefed reporters Tuesday under ground rules that their names not be used, said the plane was likely shot down by an SA-11 surface-to-air missile fired by Russian-backed separatists. The officials cited intercepts, satellite photos and social media postings by separatists, some of which have been authenticated by U.S. experts.
The intelligence officials were cautious in their assessment, noting that while the Russians have been arming separatists in eastern Ukraine, the U.S. had no direct evidence that the missile used to shoot down the passenger jet came from Russia.
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