Greek Culture Minister Pavlos Geroulanos resigned on Friday after masked armed robbers stole more than 60 objects of "incalculable" value, including a gold ring, from a museum in ancient Olympia.

Sixty-eight objects were whisked from a museum dedicated to the ancient Olympic Games after two masked men immobilised the museum's sole female guard as she arrived for her early morning shift, officials said.

The police said "bronze and clay objects and a gold ring" had been removed from display cases at the museum, which is built on a forested hilltop on the outskirts of the small town of Olympia.

"There were two of them, and they had a gun," Olympia Mayor Thymios Kotzias told Flash Radio....