(CNN)Turkish forces say they have encircled the Kurdish city of Afrin in northwestern Syria, according to Turkey's state-run Anadolu Agency, marking a major milestone in a military offensive that began in January.
Turkey says troops encircle Kurdish-held city in Syria
Turkey, a NATO ally, launched an operation targeting Kurdish groups -- some of them backed by the United States -- in Afrin province to clear the border area of militias it considers to be terrorist organizations.
Last week, Turkish President Recep Tayyip Erdogan said Turkish forces and allied Syrian rebels were poised to enter the center of Afrin -- the focus of their military campaign -- "at any moment."
Turkish forces and their allies have seized "critically important areas," according to a written statement Tuesday by the Turkish General Staff. The statement added that 3,393 militants have so far been "neutralized" -- meaning either killed, surrendered or captured -- since the start of the offensive.
Three Kurdish militias -- the Kurdish Democratic Union Party, the People's Protection Units and the Kurdistan Workers' Party -- have borne the brunt of the offensive.
Pro-Syrian regime forces are also in Afrin to support Kurdish militias along with US-backed Syrian Democratic Forces. The SDF, which was instrumental in the fight against ISIS in Syria, said it was diverting fighters from ISIS fronts to repel the Turkish offensive, prompting a Turkish outcry.
Turkish presidential spokesman Ibrahim Kalin said it is Turkey's "natural right" to ask the United States to halt the SDF's redeployment to Afrin.
The US-led coalition said the SDF move would "slow down" the fight against the terror group.
The United Nations said that it received "disturbing reports" of civilian deaths in the northwestern Syrian enclave and that it believes "tens of thousands" have been displaced.
Last week, Afrin residents told CNN they had suffered under the Turkish military offensive.
One woman, Bnafsh Jmmo, told CNN that three of her children died in an airstrike while eating breakfast.
"My future has been destroyed after my loss of my children," she said. "This deep wound will not be healed as long as I live because I lost my children and that means I've lost myself."