The Dynacom-owned MT Kerala oil tanker disappeared from radar after a suspected pirate attack off Africa's west coast, with Nigerian pirates thought to be the culprits.

"All crew members are alive and accounted for, but one is wounded and all have clearly been affected by their ordeal," Dynacom said.

Angola's navy has cast a shadow on the story though, claiming that the crew faked the attack and cut off communications deliberately.

"It was all faked, there have been no acts of piracy in Angolan waters," Captain Augusto Alfredo told Reuters.

"What happened on January 18, when we lost contact with the ship, was that the crew disabled the communications on purpose. There was no hijacking."

Alfredo declined to speculate on a motive for faking the attack.