Scores of protesters have gathered in the Greek city of Thessaloniki to protest the ratification of a deal aimed at normalising relations with neighboring Macedonia.

The protest outside the Thessaloniki Concert Hall on Sunday evening (January 27) coincided with a visit by Greek President Prokopis Pavlopoulos, who was attending a Holocaust Remembrance Day event.

Video shows protesters trying to break through police lines and being pushed back. Tear gas and stun grenades were also used, according to the filmer.

Protesters chant "traitors" while another man holding the Greece national flag blocks the road, telling drivers that if he can't enter the concert hall, then they can't move along the road.

Several arrests were made, the filmer added.

Tear gas and stun granades, protesters holding flags chanting "traitors" clash with police outside Thessaloniki Concert Hall on Sunday night. The reason is Macedonia Prespes Name Agreement and against President of Hellenic Republic, Prokopis Pavlopoulos, who is inside the Hall and watching a concept about today's Day of Jewish Holocaust. Protesters are angry for he signed Prespes Macedonia Name agreement. Soon they gone mad against police forces who protect him. Protesters blocked roads yelling at drivers, "they wont let me pass inside the Hall, you wont pass the road either" said a man with a Greek flag on his hands. Later they manage to encircle a group of police motorcyclists and threaten to beat them up, riot police interferes to save them. Oganizers of the demo are Race Committee for Greek Macedonia. After the riots, police managed to prosecute several persons, participating at the protest.