GAZIANTEP, Turkey -- Organizers say Syrian authorities have barred hundreds of activists from crossing into the country to deliver aid to victims of the Syrian regime's deadly crackdown on anti-government dissidents.

About 200 activists, mostly Syrians traveling from countries that include Bulgaria, the Netherlands, France, and the United States, gathered on the Turkish side of the border Thursday to protest the violence and deliver truckloads of food, medical aid and other supplies.

Bilal Dalati, a spokesman for the Freedom Convoy group, said Syrian authorities would not allow the convoy nor the aid in.

The United Nations estimates more than 5,000 people have died since March in Syria's crackdown.