The United Nations Office for the Coordination of Humanitarian Affairs revealed on Tuesday that an estimated 15,000 civilians have fled Afrin, in northern Syria, after the Turkish government launched an invasion of that city against the U.S.-allied Kurdish forces there.

The Turkish government insists it is making extraordinary efforts to protect civilians from the invasion, which President Recep Tayyip Erdogan argued was necessary to fight “terrorists.” While the Syrian Kurdish People’s Protection Units (YPG) have played a significant role in eradicating the Islamic State from its largest strongholds, including “capital” Raqqa, Ankara claims the YPG is a terrorist group indistinguishable from the Kurdistan Workers’ Party (PKK).

The U.S. has designated the PKK a terrorist organization but cooperates with the YPG and its all-female unit, the YPJ, on the ground in Syria.

The UN office has identified at least 15,000 internally-displaced persons (IDPs) in Afrin, the outlet Kurdistan24 reported. Many of these individuals have sought to flee from the affected areas and are “residing in houses belonging to relatives or in unfinished buildings,” according to the UN report. Many are struggling to find drinking water and are reportedly “relying on water trucks.” Those in areas where civilians have not entirely fled are also experiencing extreme price surges for basic goods that can no longer travel into Afrin safely due to Turkish aggression there.

Whether the Afrin invasion, dubbed “Operation Olive Branch,” has killed civilians is a hotly debated topic among interested parties. The Russian Foreign Ministry claimed this week that Turkey has killed “hundreds” of civilians in the area. The Syrian Observatory for Human Rights (SOHR), a UK-based NGO, has tallied 67 dead in the invasion, and nearly 200 injured.

Early this week, Kurdistan24 reported that 37 civilians have died as a result of the hostilities, identifying them mostly as women and children. To support the claims, the outlet interviewed victims, including one man who says he watched his grandchild die in his hands and saw the scattered remains of his children around him after a Turkish airstrike hit his home.

As of Monday, the Pentagon told reporters they have no intelligence suggesting that civilians have died in Operation Olive Branch. Asked about civilian casualties, Pentagon spokesman Colonel Rob Manning he had “no information” on the matter.

The Turkish government denies that any civilian casualties have occurred.

“No civilian has been harmed in Operation Olive Branch of Turkish Armed Forces and the FSA [Free Syrian Army, an Arab anti-Assad group],” Turkish Defense Minister Nurettin Canikli said on Tuesday, according to state-run outlet Anadolu Agency. Canikli insisted that the allegedly non-existent civilian death tolls “show Turkish nations’ sincerity and sensitivity” in fighting only “terrorists” and accused the YPG of using human shields.

Local civilians immediately expressed concern upon the announcement of the operation two weeks ago. Afrin is majority Kurdish with Christian and Yazidi minorities, though Turkey insists it is an Arab area. The pastor of the local Good Shepherd Church, Valentine Hanan, released a statement demanding “urgent international protection for the believers in Afrin and the cease of this Turkish shelling” when the operation began in late January. “We are also against the heavy Turkish shelling and the return of Islamic groups to the region,” the pastor added.

The Turkish government has reportedly dropped leaflets in Afrin demanding civilians “cooperate” with the invasion and boasted of significant gains on the ground.

“Since the onset of Operation Olive Branch in Afrin, 800 terrorists have been neutralized. This figure will increase by the evening,” Erdogan announced on Thursday. His government has claimed that the “terrorists” in Afrin include both YPG and Islamic State, a claim the U.S. government and the YPG have flatly denied.

The Syrian Democratic Forces (SDF), an umbrella group of which the YPG is a part, has denied that Turkey has made any gains in Afrin. On Thursday, they told the Saudi outlet Al Arabiya that at least 18 Turkish soldiers have died in the operation. In a separate interview, SDF Spokesperson Kino Gabriel affirmed that the Turkish military has failed to make any territorial gains against the battle-hardened Kurds in Afrin. On Wednesday, the SDF claimed that the Turkish government has attempted to contact them to negotiate the return of the bodies of soldiers killed in the mission.

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