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Jordanian border forces on Wednesday killed three men they said were trying to smuggle illegal drugs from Syria, the military said.
The official Jordanian news agency Petra quoted an army official as saying a soldier was in critical condition after being wounded in an exchange of gunfire.
"A large quantity of drugs was seized," said the official, without giving further details.
Wednesday's incident was the first in the area since a drone attack on January 28 in Jordan killed three US soldiers. The strike on a base called Tower 22 took place a few hundred metres from the border with Syria and was linked to the war between Israel and Iran-backed militant group Hamas.
US forces this month hit Iran-backed targets in Iraq and Syria in what Washington described as a first wave of strikes in retaliation for the three deaths.
The frontier has been the site of a low-level drugs war, which has prompted Jordan to launch military operations against smugglers in regime-controlled areas of Syria, where Iran has a strong influence.
The drugs war started in 2018, leading Jordan to fortify its border defences with help from the US.
That same year, a deal between the US, Israel and Russia resulted in the disintegration of western and Arab-backed rebel groups fighting President Bashar Al Assad in southern Syria, and the handing of the area to loyalist forces, including pro-Iranian armed groups.
Arab security officials say the drugs flowing from Syria mainly comprise the Captagon amphetamine, which is produced in government areas south of Damascus, as well as hashish that originates from Lebanon's Bekaa Valley, an area where Hezbollah holds strong influence.
Some of the drugs are consumed in Jordan but a large proportion, especially Captagon, is re-exported through illicit means to markets in the Gulf and other neighbouring countries.
