Police have arrested six people on suspicion of being members of a migrant smuggling ring which was holding 21 illegal immigrants hostage in two warehouses north of Athens until their relatives paid ransoms for their release, officers said yesterday.

Police raided the warehouses in Avlona, some 45 kilometers north of Athens, on Saturday and arrested four Pakistanis, a Syrian and a Romanian woman who are alleged to have helped smuggle some 70 illegal immigrants into the country on Friday in two small boats that set sail from Turkey.

The 21 immigrants found in Avlona, including a mother with her seven children, were all Bangladeshi. Police are investigating what happened to the rest of the immigrants and trying to track down other gang members.

The suspects made the immigrants contact their families at home and tell them to pay up to 6,000 euros for their release, officers said.

In a similar case, three Iraqis and a Tunisian were arrested in central Athens on Friday after officers found 20 illegal immigrants being held to 3,000-euro ransoms in a derelict house.