ATHENS – Greek police destroyed an improvised bomb found across the street from a police station in an Athens suburb, authorities said Monday.

The bomb, which included nails, was hidden in a bag and consisted of explosives packed into a pipe and set to a timing device. It was found just inside the perimeter fence of a university campus by a police officer, who notified explosives experts.

Police cordoned off the area and carried out a controlled detonation to destroy the device.

Authorities said there was no warning call and no immediate claim of responsibility. It was not immediately clear who planted the bomb or what the motive might have been.