Pentagon officials have confirmed that U.S. military drones were harassed three times in three days by Russian aircraft in Syria. On Sunday, the U.S. Central Command announced that it had carried out a drone strike that killed an ISIS leader in Syria and that the drones had been harassed by Russian aircraft earlier in the day. The incidents occurred on Thursday and Wednesday, where Russian aircraft allegedly engaged in unsafe behavior in front of the drones. The U.S. military has declassified videos showing the Russian jets dropping flares in front of the drones. U.S. Air Forces Central stated that Russian aircraft flew 18 unprofessional close passes that endangered the drones. The U.S. has been conducting raids and operations against suspected ISIS operatives in Syria, targeting its surviving leaders. ISIS remains a significant threat within the region, and U.S. military commanders are committed to its defeat. This recent confrontation marks the third incident this year between U.S. and Russian aircraft. In March, a Russian jet collided with a U.S. MQ-9 drone, forcing it to crash into the Black Sea. U.S. Defense Secretary Lloyd Austin called on Russia to operate its military aircraft in a safe and professional manner.