A Russian warplane was shot down near Turkey's border with Syria Tuesday morning, with Moscow and Ankara giving conflicting accounts of the incident.
However, according to Russia's state-run Interfax agency, the country's Defense Ministry said the plane crashed in Syria, and was flying over Syrian territory.
As of Tuesday afternoon, a spokesman for the Pentagon told reporters that the U.S. was still trying to determine exactly where the jet was when it was hit.
Speaking at a news conference with French President François Hollande, President Obama said Turkey has a right to defend its airspace.
"I think its important right now to make sure the Russians and the Turks are talking to each other," Obama said. That way they can figure out exactly what happened and avoid any escalation.
Russian President Vladimir Putin, meanwhile, said the fighter jet crashed on Syrian territory 4 kilometers (2.5 miles) from the Turkish border, and was shot 1 kilometer (0.6 miles) from the border.
Putin called the incident "a stab in the back by the accomplices of terrorists" and vowed it would have "serious consequences" for Russian-Turkish relations.
Speaking live on state-owned TV channel Rossiya 24, Putin did confirm that the jet was shot down "air-to-air." Earlier, Russia's Ministry of Defense had said the plane was "most likely" shot down from the ground.
This video from Andalou Agency purports to show the crash from another angle.
Russia's Ministry of Defense later tweeted that "objective monitoring data" proves the warplane remained over Syrian territory at all times.
According to preliminary data, one of the SU-24 pilots was killed in the air by ground fire in Syria, Russia's General Staff said.
The fate of the other pilot is not yet known.
A spokesperson of FSA's 10th brigade said he saw the Russian warplane penetrated Turkish airspace four times, and then was shot by a Turkish F-16.
"The rebels shot the pilot when he was parachuting down, and we are still looking for the second pilot," Jahed Ahmad told BuzzFeed News in a phone interview. "Maybe he fell in the regime area, we are not sure yet."
A spokesperson for Syrian rebel group the 10th brigade in the Coast reportedly told AP that rebels shot at the pilots after they ejected, and one landed dead on the ground.
A video from the group has circulated on YouTube claiming to show the dead body, which verification site Bellingcat said did indeed show a deceased Russian pilot wearing a uniform similar to that worn by service personnel carrying out airstrikes in Syria. However, there has been no official confirmation as to either pilot's fate.
A Syrian activist who asked to be identified as Abu Haron told BuzzFeed News he was with the rebels when they shot at the Russian pilot as he parachuted away from the jet. Haron told BuzzFeed News that the rebels thought the pilot may have bombs or a gun.
"He already had fragments in his body, so he must have died as he left the plane," Haron added.
BuzzFeed News also obtained two photos of items purportedly from the pilot's pockets.
A statement from Turkey's General Staff said the jet was warned 10 times in five minutes and challenged by two F-16 warplanes, the semiofficial Andalou Agency reported.
Army Col. Steve Warner, Pentagon spokesman for Operation Inherent Resolve, told BuzzFeed News that U.S. forces who were able to hear radio dispatches confirmed that Turkey issued several warnings before shooting down the aircraft.
Warner spoke about the incident, but clarified that this is not an incident that involves Operation Inherent Resolve, the U.S. military intervention against ISIS. He was unable to confirm whether or not the jet had entered Turkish airspace but said that the U.S. was looking into available radar data.
"We have radars and other acquisition capabilities in place and we are able to track all of the aircraft in those areas," Warner said. "We're still gathering all of the facts and looking at all of the details."
At a news conference, Pentagon spokesman Peter Cook reiterated Obama's comments about Turkey having the right to defend its airspace. He added that despite tracking radar and radio calls from the incident, the U.S. hasn't been able to conclude definitively where exactly the aircraft was when it was shot down.
"Some of the details we're trying to find out ourselves," Cook told reporters. "As the Turks have described it, they warned the aircraft in advance and that aircraft did venture into Turkish airspace."
Cook said the warplane was not in ISIS-controlled territory, adding that Russia would "be much better off" if the country focused going after the religious extremist group. Turkey had previously expressed concerns to Russian about two previous incursions into its airspace.
Turkey has requested an extraordinary NATO council meeting regarding the downed jet, which will take place at 5 p.m. Brussels time (11 a.m. ET), the Times of London and AFP reported.
The Turkish Ministry of Defense released an image purporting to be of the flight radar track of the downed warplane, CNN Turk reported.
In the image below, the red line shows the Turkish military's account of the path of the plane, with the blue line showing Turkey's border with Syria, with Turkey to the north.
Footage from Turkey's Haberturk network purports to show the jet crashing near the Turkmen Mountain area in Hatay province.
Kremlin spokesman Dmitriy Peskov described the downing of the jet as a "very serious incident," according to Reuters.
Turkish President Tayyip Erdogan was briefed by the head of the military following the crash, while Prime Minister Ahmet Davutoglu ordered the foreign ministry to consult with NATO, the U.N., and related countries, Reuters reported.
Another Russian was killed when Syrian rebels shot at a rescue helicopter, Russia's General Staff said.
The Syrian insurgent group, who has received U.S. Tow missiles, forced the helicopter to land near a government-held area in the Latakia province and then destroyed the aircraft with a missile, the Syrian Observatory for Human Rights told Reuters.
NATO Secretary General Jens Stoltenberg called for "calm and de-escalation" during a news conference held after a North Atlantic Council meeting requested by Turkey to address the situation.
He rejected any suggestion that the incident happened outside of Turkey's borders based on assessments the council received from ally countries and Turkey.
"We stand in solidarity with Turkey and support the territorial integrity of our NATO Ally, Turkey," he said.
This post has been updated to remove a photograph purporting to be of the crashed plane that was mislabeled by a photo wire service provider. The same photo was also used in the background of a tweet retweeted by BuzzFeed News.