KIEV, Ukraine (KABC) --At least one American was killed on the Malaysian plane that was shot down in Ukraine, President Barack Obama said Friday.
The American victim was identified as Quinn Lucas Schansman, a male U.S.-Dutch citizen.
A State Department official said no one used a U.S. passport to check in to Malaysia Airlines Flight 17, but officials could not rule out other individuals who may have had dual citizenship.
The passengers on the plane were from nearly a dozen nations. They included vacationers, students and a large contingent of scientists heading to an AIDS conference in Australia.
Victims' nationalities included 189 Dutch, 27 Australians, 44 Malaysians, 12 Indonesians, 4 Belgians, 1 Canadian, 3 Filipinos, 4 Germans, 1 New Zealander and 9 British. U.N. Under-Secretary-General Jeffrey Feltman told the Security Council that 80 children were on the plane.
One of the passengers attended college in the United States. Indiana University said Friday that one of its students, 25-year-old Karlijn Keijzer, a native of Netherlands, was among the passengers on the plane. It's unclear if Keijzer held dual citizenship.
Flight MH17 was shot down Thursday near the Russia-Ukraine border, killing all 298 people on board. The plane was heading to Kuala Lumpur from Amsterdam when it crashed in rebel-held territory.
Emergency workers searching the wreckage have located 181 bodies so far, and are still combing the wreckage. Bodies and body parts remain scattered around the countryside, some found Friday in a beautiful garden of sunflowers.
Some passengers will remain marked with nothing more than a white strip of cloth tied to a stick until they are collected.
"When you see wreckage and people still strapped in their seats along a path of five, 10 miles like we have here, it indicates the airplane most definitely split up at higher altitude," ABC News Aviation Consultant John Nance said.
PHOTOS: Malaysia Airlines Flight MH17 crashes
European Union officials said that Ukraine has first claim on the plane's two black boxes, a flight data recorder and a cockpit voice recorder, which could contain valuable clues about what happened in the moments before the crash.
Ukraine has called for an international probe to determine who attacked the plane, and the Unites States has offered to help. But access to the site remained difficult and dangerous. The road from Donetsk, the largest city in the region, to the crash site was marked by five rebel checkpoints.
International investigators arriving on the scene late Friday said they weren't able to properly do their jobs, followed constantly by armed pro-Russian separatists.
U.S. officials believe the plane was shot down by a surface-to-air missile, but it is unknown who fired it. The Ukraine government in Kiev, the separatist pro-Russia rebels they are fighting in the east and the Russian government all deny shooting the passenger plane down. Moscow also denies backing the rebels.
"There's no way our forces could be engaged in any way in this incident or in any other incidents all around," Ukraine's Foreign Minister Pavlo Klimkin said.
Russian President Vladimir denies his country's involvement, but it's becoming more difficult to make that claim. On Friday, Ukraine released more audio tapes they say show a Russian intelligence officer discussing the missile launcher with a pro-Russian rebel.
The U.S. has begun building a case that would blame the downing of the passenger jet on separatist forces supported by Russia. Mr. Obama says the missile was shot from an area controlled by separatists. He adds it wasn't the first time the separatists had shot down planes in the region and that a steady flow of support from Russia includes heavy weapons and anti-aircraft weapons. The president says officials from the FBI, including a forensic expert, and the National Transportation Safety Board are on their way to Ukraine to help determine what happened.
"This was a global tragedy. An Asian airliner was destroyed in European skies filled with citizens from many countries, so there has to be a credible international investigation into what happened," said Mr. Obama. "The U.N. Security Council has endorsed this investigation and we will hold all its members, including Russia, to their word in order to facilitate that investigation. Russia, pro-Russian separatists and Ukraine must adhere to an immediate ceasefire. Evidence must not be tampered with."
The United Nations Security Council called an emergency meeting Friday, during which U.S. Ambassador to the U.N., Samantha Power, pledged a full investigation.
At the start of Friday's emergency meeting, all diplomats in the crowded council chamber rose to their feet and bowed their heads in silent tribute to those who died. Ambassadors from all countries with passengers on the flight - Netherlands, Malaysia, Australia, Indonesia, United Kingdom, Germany, Belgium, Philippines, Vietnam, Canada, New Zealand and the United States - all spoke, demanding an independent investigation and calling for the perpetrators to be brought to justice.
"To the families and friends of the victims, it is impossible to find words to express our condolences. We can only commit to you that we will not rest until we find out what happened," Power said.
She later called on Russia to bring a cease-fire between the two border nations.
"Russia can end this war," she said. "Russia must end this war.
Putin on Friday said all parties in the conflict in eastern Ukraine should lay down the arms and engage in talks, according to Russian news agencies.
Why are passenger planes flying over war zones?
Separatist rebels and Ukrainian government forces have been fighting for months, killing more than 400 people and displacing tens of thousands. Many are questioning why the passenger plane was flying over the war zone.
Nance says the warning signs were there. Bulletins were issued to carriers months ago to use extreme caution when flying over active war zones, such as exists in Ukraine. But, Nance says, avoiding it would have extended flight times.
"There are two immediate reasons that come to mind for flying over a combat zone: One is that they don't realize how hot the situation is below and what the potential is, and if they've been told they can go above 32,000 feet and they're alright, they're going to do that," Nance said. "Secondly, it's because it's the shortest distance between two points.
Just this week, the ceiling of the no-fly zone was raised from 26,000 feet after several military planes were fired upon, and yet there were as many as 300 commercial airliners scheduled to fly over Ukraine Thursday just before tragedy struck.
Malaysia Airlines Flight 17 was flying at 33,000 feet, the lowest allowable altitude for a plane flying in that zone, but clearly it wasn't high enough.
"Anytime you've got a war on the ground and it's escalating, we need to steer clear of that, period, for commercial aviation," Nance said.
The Associated Press contributed to this report.