THESSALONIKI, Greece (AP) — Greek police have arrested six people who they say are members of a large human trafficking gang that violently extorted money from migrants to assist them in crossing into neighboring Albania and travel to European Union countries to the north.

The six suspects — a Syrian, a Palestinian and four Iraqis — were arrested Saturday at a village less than 10 kilometers (six miles) from the Albanian border, police said Sunday.

Seven more members of the gang were arrested in the same area on Sept. 28. At that time, 11 migrants had been found detained in shacks and abandoned military outposts.

Police had said in September that the traffickers, who had already collected upwards of 1,000 euros (nearly $1,100) from each of the migrants to help them cross into Albania, had detained them, demanding an additional 1,500 euros ($1,640). Police said the traffickers tortured the migrants, videotaped the torture sessions and sent the footage to the victims’ relatives in the Middle East and South Asia.

This time, no migrants were found with the traffickers.

Police say they are searching for seven other members of the gang still at large.