Aboard a US military plane in the Middle East (CNN)A Russian fighter jet and a US military plane flew dangerously close to each other while flying over Syria earlier this month, according to the Pentagon.
US Air Force Lt. Gen. Jeffrey Harrigian, who commands US air operations across the Middle East, characterized the incident as a "near miss."
Both planes were flying at hundreds of miles an hour with their lights off on the night of October 17. The US military plane came within less than half a mile of the Russian jet, close enough to be in the jet wash of the Russian plane, according to US military officials.
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At a time of deepening tensions between the United States and Russia over Russia's role in the Syrian war, the near miss underlines how the intensifying conflict in Syria could make those tensions even worse.
A US military official said that given these existing tensions, should an American and Russian military plane collide over Syria, "people will not interpret this as an innocuous mistake."
Harrigian said the likelihood of such incidents had increased in the past six weeks because the United States has moved additional aircraft into the air above northwest Syria as the operation to take the Syrian city of Raqqa from ISIS starts to ramp up.
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Aware of the risks of either a mid-air collision between US and Russian planes or of Russian planes bombing US Special Forces inside Syria, the US military has set up a hotline with the Russians.
On the night of the near miss earlier in October, the US military pilot followed normal procedure and contacted the Russian pilot over an emergency frequency. The Russian pilot did not respond, according to the US military.
On October 18, the day after the near miss, a US military official who speaks Russian contacted his Russian counterpart over the hotline. The counterpart said the Russian pilot hadn't been aware of the incident.