(CNN) -- An oil tanker seized by pirates off the west coast of Africa has been released by the hijackers, the operators of the vessel said.
An official with Golden Energy Management, the Greek company that chartered the ship, said the Energy Centurion was released Thursday, some 60 miles east of Lagos, Nigeria, and was steaming toward a "safe port."
The official said all 24 crew members -- mostly Russian -- who are still on board the ship are safe. They were not harmed by the hijackers, he said.
The official said the Energy Centurion held 57,000 tons of gas oil on board and about 3,000 tons was stolen by the pirates.
The company will also have to evaluate the state of the ship, the official said, after the pirates damaged some electronics and communications equipment.
The Isle of Man-flagged vessel was hijacked early Tuesday off the coast of the Togolese capital Lome, where it was anchored.
Once on board, the pirates exchanged gunfire with a Togo naval ship that responded to a distress call, before they disappeared off the coast of neighboring Benin.
This is the second such attack in less than two weeks in the Gulf of Guinea, off the west coast of Africa.
There has been an increase of attacks in the region, according to a recent report from the International Maritime Bureau's Piracy Reporting Center.
While Somali piracy remains a serious threat, a recent report from the center said there were 32 attacks this year alone in the Gulf of Guinea.