The Turkish Armed Forces (TSK) and the Free Syrian Army (FSA) have liberated five more villages – Hantalli, Divan Tahtani, Ikidam, Shaltah and Marsawiyah – as well as a hill and a strategic base from the PKK-affiliated People's Protection Units (YPG) in northwestern Afrin, Syria, the TSK said in a statement Monday.

The number of areas liberated from terrorists since Operation Olive Branch was launched has increased to 74, including 52 villages and 18 strategic hills and mountains.

Additionally, according to Anadolu Agency (AA) correspondents on the ground, the number of terrorists killed has reached 1,641.

Turkey launched the military offensive on Jan. 20 to remove the PKK terrorist organization's Syrian affiliate, the Democratic Union Party (PYD) and its armed wing the YPG, as well as Daesh from northwestern Syria.

On Monday, the TSK and the FSA liberated Nabi Houri Hill, which is home to the historical Nabi Houri Castle that dates back to the Roman era.

According to the Turkish General Staff, the operation aims to establish security and stability along Turkish borders and in the region as well as to protect Syrian people from the oppression and cruelty of terrorists.

It added that the operation is being carried out under the framework of Turkey's rights within international law, U.N. Security Council resolutions, its right to self-defense under the U.N. charter and respect for Syria's territorial integrity. The military also said the "utmost importance" is being placed on not harming any civilians.

The operation in Afrin – bordering Turkey's Hatay and Kilis provinces – was widely expected in the wake of Operation Euphrates Shield in northern Syria, which cleared Daesh terrorists from the country's border from August 2016 to March 2017.

Afrin has been a major hideout for the YPG, since July 2012 when the Bashar Assad regime in Syria left the city to the terror group without putting up a fight.

Meanwhile, at least four people were killed on Sunday by a car bomb blast in Syria's northeastern Qamishli, a war monitor said. The Syrian Observatory for Human Rights said another three people were also wounded when "an explosion went off inside a car in the city's Al-Gharbi neighborhood."

Rami Abdel Rahman, the head of the British-based Observatory, could not confirm whether the casualties were civilians or combatants. Syrian state news agency SANA also reported the blast but listed the death toll as five people. Qamishli is mostly under the control of the YPG, though Assad regime forces have a limited presence in the city's "security quarter."