TUNIS, Tunisia (AP) — Hurling stones and wielding clubs and knives, dozens of supporters of Tunisia’s Islamist rulers attacked members of the country’s main labor union on Tuesday, in the latest sign of unrest in the North African country.

Activists with the General Union of Tunisian Workers were gathering for a march in Tunis to commemorate the 1952 assassination of a historic member when they were set upon by the League for Protection of the Revolution, resulting in pitched battle that injured 10 people before police restored order.