The United States military shot down a suspected pro-regime drone that fired on coalition forces in southern Syria on Thursday, according to the U.S.-led coalition spokesperson.

Colonel Ryan Dillon said that the drone was armed and fired on coalition forces operating outside of the de-confliction zone around Al Tanf. There were no coalition casualties, Dillon said during a briefing in Baghdad.

The drone was similar to a U.S. MQ-1 Predator, he said.

Map showing location of At Tanf, Syria Google

U.S. Central Command (CENTCOM) said in a statement later Thursday that the pro-regime drone was shot down by U.S. aircraft after it dropped one of several weapons it was carrying near a position occupied by coalition personnel who were training and advising ground forces there in the fight against ISIS.

The U.S. also conducted strikes against two technical vehicles Thursday morning,which were pick-up trucks with weapons that posed a threat to the U.S. and the coalition forces at Al Tanf Garrison, Dillon said.

This is the third set of strikes the U.S. has conducted in defense of U.S. and coalition forces at Al Tanf. The three were an air to ground strike on May 18, air to ground on June 6 , and one air to ground on the trucks and and one air to air on the drone on Thursday.

CENTCOM said in its statement that the coalition "does not seek to fight Syrian regime, Russian or pro-regime forces partnered with them," but added that "the demonstrated hostile intent and actions of pro-regime forces near Coalition and partner forces in southern Syria, however, continue to concern us and the Coalition will take appropriate measures to protect our forces."

The airstrike in May appeared to be the first publicly known direct confrontation between U.S. forces and fighters loyal to Syrian President Bashar al-Assad.