A Malaysia Airlines Boeing 777, MH-17, has crashed in eastern Ukraine, en route to Kuala Lumpur, the airline has confirmed, with 295 people on board. The airline has scheduled a press conference for 4pm ET to provide more details.

The Russian news agency Interfax first reported that the flight was shot down by a missile, citing an adviser to Ukraine’s interior minister, Anton Gerashchenko. On his Facebook page, Geraschenko blames separatists using a “Buk” anti-aircraft missile system obtained from Russia.

Separatist officials in the region denied having anything to do with the crash, saying they didn’t have the ability to hit a plane at the height the Malaysia Airlines jet was flying.

The airspace over Ukraine is contested as the government battles pro-Russian separatist militias there, following Russia’s annexation of Crimea. Ukraine today accused Russia of downing a military jet with a missile in the same region. Commercial airliners now appear to be diverting away from the area:

With geopolitical tensions already high in the region, any sign of Ukrainian, Russian or separatist involvement in the downing of an airliner could lead to a serious escalation. Ukraine’s government, already accusing the insurgents of causing the crash, will seek to tar Russia as a disruptive force in the region, rallying international pressure to its side. Russia, on the other hand, can be expected to make the case that the tragedy is a clear sign that Ukraine’s government cannot control its own airspace, as it has after past accusations. In 2001, Ukrainian’s military accidentally shot down a Russian passenger jet over the Black Sea.

The situation is reminiscent of Cold War tensions that led to the downing of Korean Airline Flight 007 by a Russian missile in 1983 while it flew from Seoul to New York City. The Soviet Union denied that it was involved in the attack, which occurred within Russian airspace, but later admitted culpability. There are also similarities to when a US navy ship shot down Iran Air 655 in 1988 while patrolling the Persian Gulf at a time of similar tension, mistakenly believing the aircraft was a threat.

The crash also marks another tragedy for Malaysia Airlines, which infamously lost track of another jet, MH-370, that disappeared somewhere over the South Pacific in March. There is still no official explanation for its disappearance, though the search for the plane and its passengers continues.

Here’s Malaysian prime minister Mohd Najib Tun Razak’s statement on Twitter:

These journalists appear to have arrived at the location of the crash:

This story originally appeared on Quartz, a Skift content partner.

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Photo Credit: Screen grab from live online coverage by ABC News. ABC News