The Kurdish People's Protection Units (YPG) is the main fighting element of the Syrian Democratic Forces (SDF), which has acted as the principal allies of the USA in a campaign that recaptured territory held by the ISIL group.
Turkish troops and Turkish-backed Syrian rebels gather outside the border town of Ras al-Ain.
The SDF had earlier reported that a group of "mercenaries of the Turkish army" had killed a number of civilians on the road after infiltrating the area, without identifying them. This was stated by a senior Turkish official, Reuters reports.
"They know exactly where US forces are", Milley said at a joint Pentagon news conference with Defense Secretary Mark Esper.
Ras al-Ain would be the first town to fall to Ankara's forces since the launch of its cross-border offensive on Wednesday.
For his part, Saudi Foreign Minister Adel al-Jubeir described the Turkish assault in northeastern Syria as "a blatant aggression on the Syrian sovereignty", warning that it might lead to the reappearance of IS militants and other terrorist groups.
In his remarks during the meeting, AL Secretary-General Ahmed Aboul-Gheit described the Turkish offensive in northern Syria, which Ankara refers to as "Operation Peace Spring", as "a military invasion".
As self-defense, the terrorists positions were targeted, Akar said.
Following Newsweek's report, a Pentagon spokesperson, Navy Captain Brook DeWalt, said in a statement that "the explosion occurred within a few hundred meters of a location outside the Security Mechanism zone and in an area known by the Turks to have USA forces present".
Blizzard staff walkout to protest Blitzchung ban for Hong Kong comments
Prominent Hearthstone caster and analyst Brian Kibler will not be casting the Hearthstone Grandmasters finals at BlizzCon. The league struggled with its initial response to blowback from Chinese companies and its domestic basketball league.
Hello, Beautiful: Second-gen 2021 Toyota Mirai Concept is Unveiled
This latest generation of Mirai also has a larger hydrogen capacity, and a target 30-per-cent increase in driving range. The platform accommodates different vehicle sizes and also front-, rear- and all-wheel drive configurations.
Apple, Google Remove Hong Kong Map After China Backlash
Apple's move, it said, was "clearly a political decision " created to suppress freedom and human rights in Hong Kong. In a Wednesday statement , Apple said that it had heard concerns about the app from many Hong Kong customers.
The SDF holds most of the northern Syrian territory that once made up Islamic State's "caliphate" in the country, and has been keeping thousands of fighters from the jihadist group in jail and tens of thousands of their family members in camps.
Turkey's defence ministry said it "neutralized" 415 Syrian Kurdish fighters. Trump has been criticized for "abandoning" the Kurds, who were U.S. allies in the fight against Islamic State (IS, formerly ISIS).
"Most of the Syrian National Army fighters, the friendly indigenous components of the operation, are local Arabs and Turkmens from the region", he said.
Stoltenberg spoke at a news conference in Istanbul with Turkish Foreign Minister Mevlut Cavusoglu.
After overnight clashes with Kurdish forces in the countryside, Turkish troops and their Syrian allies entered the battleground town of Ras al-Ain, sources on both sides said.
Turkey said 415 YPG militants had been "neutralized" since the operation began, a term that commonly means killed.
Turkey's state-run Anadolu news agency said that Turkey-backed Syrian opposition forces had taken control of the M-4 highway that connects the towns of Manbij and Qamishli. It did not say if any Islamic State prisoners had escaped.
SDF spokesman Marvan Qamishlo said they had only carried out a "tactical retreat" in response to hours of heavy Turkish bombardment.
France has suffered multiple deadly attacks by IS-linked radicals.