Authorities in the region of Thebes northwest of Athens have freed a migrant farmhand found imprisoned in a ship’s container and forced into effective slave labor by other migrants, police said Monday.

A police statement said three men, including an under-age youth, were arrested and face charges of human trafficking and breaching immigration laws. The operation followed a tip-off by email.

Police said the alleged victim had been talked three months ago by the suspects into working with them in farms near Thebes. But when he reached the area he was allegedly exploited, with the suspects taking most of his daily earnings, locking him up at night and beating him when he asked for his wages.

The nationalities of the victim and the suspects were not made public.