Seven people have been arrested on suspicion of abducting a 26-year-old man in the Peloponnese in August and demanding a 620,000-euro ransom from his family.
The victim has not been seen or heard from since August 17.
Police said the seven suspects, six men and one woman, include a 71-year-old man who was a friend of the victim’s parents.
The 26-year-old disappeared after leaving Diakofto to head for a meeting in Aigio. His car was found days later in Athens.
The suspects have refused to reveal where their victim is or if he is alive.
Police said they were planning to abduct the 26-year-old’s mother after the family failed to pay the ransom the gang demanded.