A terrorist explosive hit a joint patrol of Turkish and Russian troops in northwestern Syria, causing damage but no casualties, Turkey's National Defense Ministry announced on Tuesday.

Troops carrying out their 21st joint patrol in the Idlib, Syria cease-fire zone had their vehicles targeted by a roadside explosive, said a ministry statement.

There was no loss of life but two vehicles in the convoy suffered partial damage, it added.

The joint patrols will continue with determination and all necessary measures, it stressed.

The terrorist group was not named, but the YPG/PKK has been active in the region.

In its more than 30-year terror campaign against Turkey, the PKK – listed as a terrorist organization by Turkey, the US and EU – has been responsible for the deaths of 40,000 people, including women, children, and infants. The YPG is the PKK’s Syrian offshoot.

This March, Ankara and Moscow reached a deal urging parties to "cease all military actions along the line of contact” in the de-escalation area in Idlib, an embattled Syrian opposition-held province just south of Turkey’s border.

The protocol said joint Turkish-Russian patrols would begin on March 15 along the M4 highway in Idlib.

Idlib has long been under siege by Assad regime forces and its allies, and previous cease-fires for the region were plagued by violations.

Turkey has worked to protect the local civilian population as well as rid the wider region of terrorist elements.