Two US military service members were “physically attacked” in the port city of Izmir in western Turkey on Monday by members of an anti-American youth group, authorities said, writes The Guardian.

15 suspected assailants were detained in the attack on the 2 service members, who were dressed in civilian clothing at the time of the incident. 5 other US service members joined in the incident after seeing the violent encounter.

Those detained were members of the Turkey Youth Union (TGB), a youth offshoot of the nationalist opposition Vatan Party. Police intervened in the incident and authorities are conducting an investigation, officials said.

“We can confirm reports that US service members embarked aboard the USS Wasp were the victims of an assault in İzmir today, and are now safe”, the US embassy to Turkey said on X. “We thank Turkish authorities for their rapid response and ongoing investigation.”

The US embassy in Ankara said earlier Monday that the Wasp was on a port visit to Izmir, a coastal town. The ship arrived on Sunday following joint training with Turkish military ships in the Mediterranean.