On Sunday, a Syrian government fighter jet was shot down by a U.S. aircraft hours after Syrian forces bombed U.S.-backed fighters in a village southwest of Raqqa, the Pentagon said. This was the first time a U.S. jet downed a manned hostile aircraft in more than 10 years, The Washington Post reports, and the fourth time in a month that the U.S. military attacked Syrian loyalist forces. In a statement, the Syrian military said the jet was carrying out a mission against the Islamic State, and its pilot was killed. On Monday, Russia, which supports Syrian President Bashar al-Assad's forces, responded by declaring it would treat U.S.-led coalition aircrafts that crossed west of the Euphrates River as targets.

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