Following the Malaysia Airlines Flight 17 crash Thursday — which killed all 298 on board — many questions still remain.
USA TODAY Network lists what we know now about the downed plane as countries seek answers:
Where are the black boxes?
Rebel forces believed to be responsible for the downing of the airliner handed over both black boxes from Flight 17 to Malaysian investigators who are in the Ukraine.
A senior separatist leader, Aleksander Borodai, gave the data recorders to a delegation from Malaysia in Donetsk early Tuesday.
What is the role of the United Nations?
With Russia's support, the U.N. Security Council on Monday approved an international investigation into the jet crash.
The resolution also calls for a stop to all military activities around the crash site in the eastern Ukraine and for Russian-backed separatists to allow international investigators complete access to the site. The resolution passed unanimously.
What is President Obama's stance on the investigation?
Obama called on Russia Monday to get pro-Russia separatists to stop impeding the crash investigation and allow international experts free and unfettered access to the site.
"Families deserve to be able to lay their loved ones to rest with dignity," he said in Washington. The president urged Russian President Vladimir Putin to take action on the investigation.
"Given its direct influence over the separatists, Russia — and President Putin in particular — has a direct responsibility to compel them to cooperate with the investigation. That's the least they can do," Obama said.
What challenges are investigators facing at the crash site?
Dutch investigators arrived in eastern Ukraine Monday and began inspecting the bodies of victims that had been stacked in refrigerated railway cars by separatists. The train left Monday afternoon from for the city of Kharkiv, controlled by the Ukraine national government, en route to Amsterdam.
On Sunday, armed rebels reportedly denied investigators access to the crash site.
"Malaysia is very concerned that the sanctity of the crash site has been severely compromised," Malaysian Minister of Transport, Liow Tiong Lai, said in a statement Sunday from Ukraine, where he is leading a team of investigators from his country.
FULL COVERAGE: Malaysia Airlines Flight 17
The Ukrainian government and separatists agreed Saturday to set up a security zone around the crash site of the Malaysia Airlines jet to allow the orderly removal of the bodies.
Who was on board Flight 17?
The Boeing 777 was carrying 298 people. The victims came from 11 countries.
The victims include 193 Dutch (including one dual Netherlands/U.S. citizen), 43 Malaysians (including 15 crewmembers and two infants), 27 Australians, 12 Indonesians (including one infant), 10 Britons (including one dual U.K./South Africa citizen), four Germans, four Belgians, three Filipinos, one Canadian and one New Zealander, according to the flight manifest released by Malaysia Airlines on Saturday.
Malaysia Airlines and foreign embassies have "made every effort to establish contact with the next-of-kin" of the dead but still are unable to "identify many more family members," the airline said in a statement.
What kind of missile shot down the plane?
U.S. officials say it was a SA-11 surface-to-air missile that downed the Boeing 777. It is also known as a Buk, which was first built by the Soviet Union and is capable of shooting aircraft traveling up to 70,000 feet.
Who took down the jetliner?
Although Russia and separatist leaders have denied responsibility for shooting down the plane, U.S. Secretary of State John Kerry said Sunday there was mounting evidence that a Russian-made missile, an SA-11, brought down the airliner.
Where was the airliner headed?
The Malaysian airliner was en route from Amsterdam to Kuala Lumpur with 283 passengers and 15 crewmembers when it crashed into rebel-held territory in eastern Ukraine.
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