US intelligence has confirmed that a Malaysian passenger plane carrying 298 people was shot down, reportedly with a Buk ground-to-air missile, over Ukraine near the Russian border, echoing a report issued by an advisor to Ukraine's Interior Minister. The advisor, Anton Gerashchenko, posted more accusations on Facebook, saying that the strike was carried out by Ukrainian rebels. He also posted a minute-long video of what supposedly is the smoking wreckage of the plane. A Reuters correspondent on the scene has confirmed the "burning wreckage of airplane, bodies on ground." A Ukrainian separatist leader, meanwhile, has blamed the crash on the Ukrainian military. President Petro Poroshenko has stated that the "armed forces of Ukraine did not take action against any airborne targets."

A US official who confirmed the attack said that analysts were still trying to figure out who fired the missile. "It's going to take time to get some information on the intentions of whomever was involved." Vice President Joe Biden, who said that he had spoken with Poroshenko for half an hour about the plane, said it was "shot down, not an accident, blown out of the sky." The nationalities of all 283 passengers are not known, but Malaysia Air has released a partial count that lists over half as Dutch, 27 Australian, and 30 Malaysian, with other passengers coming from Indonesia, the UK, and elsewhere. All 15 members of the crew were Malaysian.

The Boeing 777 flight, Malaysia Airlines 17, was en route from Amsterdam to Kuala Lumpur. In a statement, Malaysia Airlines has confirmed that it lost contact with the plane over Ukrainian airspace around 30 miles from the Russian border, but the cause is still officially unknown. The Malaysian prime minister is launching an "immediate investigation" of the reports, and we'll continue to update with major developments.

Malaysia Airlines has lost contact of MH17 from Amsterdam. The last known position was over Ukrainian airspace. More details to follow. — Malaysia Airlines (@MAS) July 17, 2014

The news comes soon after Ukraine said that a Russian plane had shot down one of its fighter jets, which would mark a new level of open hostility between the countries. That report has not been confirmed, and the spokesperson for one separatist group told The New York Times that missiles were fired by Ukrainian rebels from the ground, rather than in the air with Russian support. Russia's defense minister reportedly said the accusation was "absurd."

#BREAKING: Malaysian plane was brought down by a ground-to-air missile: Interior Ministry adviser, quoted by Interfax — Reuters Top News (@Reuters) July 17, 2014

Update July 17th 4:15PM ET: Updated with Wall Street Journal report that US intelligence confirmed the missile attack, as well as details from US officials and Malaysia Air.

Update July 17th 8:04PM ET: Updated with new passenger count from Malaysia Air.