Greek police arrested a total of 44 people for illegal antiquities trafficking after they investigated the group's moves for months, officials said Sunday.

Police said they confiscated 9,200 silver and bronze coins dating from the 6th century B.C. to Byzantine times (4th to 15th century A.D.). They also confiscated 300 “small artifacts.”

The ringleader of the group, a 66-year-old retired customs official, would often travel abroad to arrange for the sale of the coins, police said. He, along with his two brothers, a daughter-in-law and another relative, formed the core of the group, while the other 39 would excavate in several places in northern and central Greece at the ringleader's request.

“We conducted 55 separate searches on Saturday,” regional police chief Vassilis Kanalis said in northern Polygyros, 580 kilometers (360 miles) northeast of Athens. “This was the culmination of a great investigation which began six months ago.”

The suspects made depositions to an examining magistrate.

The most valuable coin, according to experts, is a silver coin from the era of Alexander the Great (4th century B.C.) in which Alexander is depicted as an eagle on one side, while the other shows his father and predecessor as King of Macedonia, Philip II.

“We are talking about a huge treasure, which... was smuggled and sold abroad in small quantities,” another regional police chief, Constantine Papoutsis, said.

In the past six months, the ringleader made several trips abroad _ to Bulgaria, Switzerland, Germany, Great Britain and the U.S. _ presumably in search of clients. He traveled often, sometimes twice a week.

“The case has a lot of depth. There are likely other persons involved, whom we will look for,” Papoutsis said. (AP)