Russian families have begun the process of identifying the bodies of victims of Saturday's crash of a Russian jetliner in Egypt.
The Associated Press said the first 10 bodies have been identified.
A spokesman for Russia's emergency situations ministry told AP that a total of 140 bodies, and more than 100 body parts, were flown to St. Petersburg on two government planes Monday and Tuesday. Another plane was to deliver more remains later Tuesday.
All 224 passengers and crew aboard a Metrojet Airbus A-321 were killed when the plane went down over the Sinai Peninsula about 20 minutes after takeoff from the airport at the Egyptian resort town of Sharm el-Sheikh on a flight to St. Petersburg. Three Ukrainians were among the fatalities.
Russian transportation officials said flight recorders recovered from the jetliner sustained only "minor" damage and have undergone a preliminary inspection.
"The black boxes were found on the first day. They received insignificant damage and after everyone involved in the investigation arrives, we'll start decoding the records.” Maxim Sokolov, Russia Transport Minister, said Monday. “We'll do everything possible to establish the causes of the tragedy with the participation of international experts."
Officials with Metrojet cited "external" reasons for the crash, after ruling out technical failure or human error.
"There are no such faults, like engine failure, system failure, there is no such combination of systems failure that could lead to a plane breaking up in the air," Alexander Smirnov, depty general director of Metrojet, said.
"Yes, under a tragic multilevel contingency when several systems fail, along with some other accompanying factors, that indeed could lead to a catastrophe. But in that case the aircraft would break up through hitting the ground. Aircraft cannot break up in the air because of a failure of any systems," Smirnov said.
Metrojet did not offer evidence to back its assertions, and Russia's air ministry later called the carrier's comments "premature and not based on any real facts."
Cairo and Moscow have played down claims from Egypt's Islamic State branch that it downed the plane.
Aviation and military experts have voiced doubt that extremists had missiles capable of hitting a target at an altitude of 9,100 meters.
In Washington, U.S. Director of National Intelligence James Clapper said he knew of "no direct evidence" linking the crash to terrorism. He also said it was "unlikely" that Islamic State had the technical expertise to carry out such an attack, but said "I wouldn't rule it out."
White House spokesman Josh Earnest said U.S. investigators had offered to help probe the disaster. But he did not say whether that offer had been accepted by Moscow.
Russia's Ria Novosti news agency quoted Russian investigator Viktor Sorochenko as saying fragments of the Airbus A-321 were "strewn over a large area." He spoke after visiting the crash site.
President Vladimir Putin promised a thorough investigation into the Metrojet crash.
"I would like to express my condolences to the loved ones and relatives of the victims. It is a great tragedy, and of course we are with you in heart and soul," Putin said Monday.
He stressed the importance of finding the cause of the crash so that authorities can take appropriate action.
Russia has sent about 100 experts to help Egyptian authorities search for the remains of victims and the aircraft debris.
Several airlines, including Air France, Lufthansa, Dubai-based Emirates and Qatar Airways, have said they will stop flying over the Sinai peninsula for safety reasons.
Egyptian Civil Aviation chief Hossam Kamal said safety checks before the flight did not turn up any problems, and he said the pilot did not issue a distress call before the plane disappeared.
VOA's Zlatica Hoke contributed to this report.
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