Two suicide bombings and another blast rocked northwest Syria near the Turkish border on Thursday, killing at least three people and wounding several others, witnesses and a war monitor said.

A rescue worker said one civilian was killed after an improvised explosive device went off in a vehicle near a transport office in the city of Azaz, which lies near the main border crossing with Turkey.

A few hours later a suicide bombing in a marketplace in the town of al-Bab wounded three and killed the suspected bomber, a police source said.

This was followed minutes later by another suicide bombing at a roundabout in the city of Afrin. The Syrian Observatory for Human Rights said it did not have a casualty toll for that attack.

It was not immediately clear if the three explosions were linked.

Main opposition towns in the northwestern border area have in the last year been frequently hit by bombings detonated in crowded civilian areas.

Turkey and opposition forces say the blasts aim to create disorder in the area, which is populated by more than 3 million Syrians who have fled regime-controlled areas during the country's decadelong civil war, ultimately making it ungovernable.

The opposition in Azaz and other parts of the enclave have blamed previous blasts on the PKK terrorist organization’s Syrian wing, the YPG, which controls some areas in the northwest and holds sway over swaths of Syria's northeast.

Afrin was largely cleared of YPG terrorists in 2018 through Turkey's counterterrorism offensive Operation Olive Branch, and was set on a path toward normalization with the restoration of several hospitals, schools and other vital facilities.

Despite all these positive developments, the YPG continues to target residential areas and civilians in Afrin by using Tal Rifaat, located in southeast Afrin, as a base. Local people living in areas held by the YPG have long suffered from its atrocities, as the terrorist organization has a notorious record of human rights abuses, ranging from kidnappings, recruitment of child soldiers, torture, ethnic cleansing and forced displacement in Syria. The YPG has forced young people from areas under its control to join its forces within the so-called "compulsory conscription in the duty of self-defense."