ATHENS — Police in Greece clashed late Wednesday with Communist-backed demonstrators who tried to prevent a concert by U.S. military cadets.

The violent protest occurred in the central Greek city of Larissa ahead of a concert by members of the West Point Glee Club, a musical group of the U.S. Military Academy which is currently on tour in Greece.

Videos and photos shared on social media show police firing tear gas to hold back the demonstrators outside a municipal theater, while officers also clashed with a smaller number of protesters as they entered the building.

It was not immediately clear if the concert took place. Authorities and the venue couldn’t be reached for comment.

Protest organizers from the Greek Communist Party oppose the presence of U.S. troops in Greece as well as Greek military support for Ukraine and involvement in international maritime security missions in the Red Sea.