KIEV, Ukraine (KGO) --International investigators arrived at the site of the deadly plane crash on Friday, but they were not able to do a full inspection because armed pro-Russian rebels are guarding it. The team spent about 75 minutes at the site of the wreckage before rebels ordered them to leave and fired a warning shot.
The United States has begun building a case linking pro-Russian separatists to the downing of a passenger jet in Ukraine.
President Barack Obama says the U.S. believes the Malaysia Airlines plane was felled by a surface-to-air missile launched from an area near the Ukraine-Russia border that is controlled by Kremlin-backed separatists. Obama cautioned that the exact circumstances are still being determined, but also said the insurgents would not be capable of carrying out such an attack without Russia's support.
The president spoke shortly after the U.S. ambassador to the United Nations, outlined preliminary evidence against Russia and the separatists during an emergency meeting of the U.N. Security Council. Samantha Power said separatists were spotted Thursday with an SA-11 anti-aircraft missile at a location close to the site where the plane came down and that they had boasted on social media sites about shooting down a plane, then later deleted those posts.
A graduate student at Indiana University who moved to the U.S. from Amsterdam and an American are among the victims who died when a Malaysia Airlines jetliner carrying 298 people was shot down by a missile in eastern Ukraine on Thursday.
Karlijn Keijzer, a 25-year-old pursuing her doctorate in chemistry, was on Flight 17. The university says she was a member of the school's rowing team during the 2011 season. She was taking a vacation with her boyfriend.
"I'm just in disbelief and expecting Karlijn to pop up on Facebook and tell everybody she's OK," Keijzer's friend Rachel Weigler told ABC News.
During a news conference, President Barack Obama also reported that an American was killed when the airline was shot down by a surface-to-air missile in an area controlled by Russian-backed separatists.
A State Department official tells ABC News that the victim, who is a U.S.-Dutch citizen, is Quinn Lucas Schansman.
The president called it a global tragedy in remarks from the White House, one day after Malaysia Airline Flight 17 crashed.
Obama also called for an immediate ceasefire in Ukraine and demanded a credible investigation of the downed plane.
The plane was shot down near the border between Ukraine and Russia. The incident occurred one day after Obama announced broader economic sanctions against Russia for its threatening moves in Ukraine.
Emergency workers, police officers, even volunteers are busy picking through the wreckage of the Boeing 777 that shot from the sky. Debris is strewn across sunflower fields.
The Ukrainians called it an act or terror. On Thursday they released what they say were intercepted messages between pro-Russian rebel commanders, proving they thought they were targeting a Ukrainian military plane.
On Friday the rebels walked back on claims that they had found the plane's black boxes. And Russia said it will not remove them from the crash scene.
But aviation experts say the black boxes may only have a couple seconds of data and won't really give any clues about those key questions of who and why.
We're learning more about the 298 passengers on board that doomed flight, the majority of whom were from the Netherlands.
As many as 108 AIDS activists, researchers, and health workers heading to a major conference in Melbourne, Australia were on the doomed plane.
The World Health Organization has also reported that its spokesperson Glenn Thomas was onboard the jetliner. The 49-year-old Briton was also traveling to attend the AIDS conference, which starts Sunday.
UN Under Secretary General Jeffrey Feltman tells the Security Council that 80 children were on board.
And an Australian woman who lost her brother in the disappearance of Malaysia Airlines Flight 370 learned that her stepdaughter was on the Malaysia Airlines Flight 17.
Kaylene Mann's brother Rod Burrows and sister-in-law Mary Burrows were on Flight 370 when it vanished in March. On Friday, she found out that her stepdaughter, Maree Rizk, was killed along with 297 other passengers on board Flight 17 when it crashed in Ukraine.
Mann's brother Greg Burrows says news of the second tragedy to hit the family has "ripped our guts again."
Rizk and her husband Albert were returning home to Melbourne from a four-week European vacation.
A Ukrainian official says 181 bodies have been located so far at the crash site. The Malaysian government is sending a 62 person team.
A senior administration official tells ABC News that FBI and NTSB officials will be headed to Ukraine in an "advisory role" in the crash investigation.
Officials are still working to confirm whether any other U.S. citizens were on board the plane.
(ABC7 News and the Associated Press contributed to this report)