A nationalist Turkish youth group attacked two US marines in western Turkey on Monday.
The marines, who were assigned to the USS Wasp, were assaulted in Izmir, with one assailant placing a bag over the head of a service member.
The incident was confirmed by officials from both countries, NBC News, Sky News’ US partner network, said.
Thirteen men and two women were detained after being accused of attacking the service members, officials in Izmir province said.
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There are no reports of arrests or charges.
They are accused of being members of the nationalist Turkish Youth Union.
Video showed the pair being surrounded by a group of people chanting “Yankee go home” on a busy street.
One of the marines was restrained before a bag was placed over his head.
Other marines intervened, and no one was injured, with the service members later returning to their ship, the US Navy said in a statement.
The two marines were taken to a hospital as a precaution.
National Security Council spokesperson Sean Savett said: “We are troubled by this assault on US service members and are appreciative that Turkish police are taking this matter seriously and holding those responsible accountable.”
Suleyman Elban, the governor of Izmir province, said: “On Monday, September 2, 2024, at around 4pm, two US citizen military personnel in civilian clothes were physically attacked by a group of 15 people, two women and 13 men, who are members of the Turkish Youth Union (TGB)”.
A statement from the governor said five plain clothes US service members were “watching from a distance” and were involved in the incident in some way.
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The TGB is a small, nationalist political party without any seats in parliament.
An account on X purporting to represent the TGB posted video of the incident on Monday, accusing US soldiers of “carrying the blood of our soldiers and thousands of Palestinians on their hands”.
The USS Wasp is an amphibious assault ship and the US embassy said it was carrying out a port visit in Izmir this week.