Former physical training instructor Billy Ideson said that he and colleagues were ritually humiliated and beaten during a brutal ceremony within hours of their passing-out parade at the corps training centre in Lympstone, Devon.
The 32-year-old former Commando corporal said that the ordeal involved him being kicked and punched as he was dragged by a rope, struck on the genitals, and thrown into a waste pit.
The Ministry of Defence said an investigation was being launched into the claims made in the News of the World yesterday but stressed the practice of unofficially "blooding" new recruits was now a thing of the past.
"The Royal Marines does not tolerate any form of initiation ceremony; however, allegations have been made through the media and they will be the subject of an investigation," said a spokesman.
"It was recognised that such rituals were getting out of hand and they were stopped a long time ago - there is no suggestion that this sort of thing is happening now."
George Robertson, the Secretary of State for Defence, has pledged a campaign to stamp out bullying and harassment in the armed forces. A confidential telephone hotline was set up last year to encourage servicemen and women to come forward.
Mr Ideson, from Exeter, Devon, told the newspaper that the initiation ceremony had featured multiple humiliations - including hot tea bags being pushed between his buttocks, and heated spoons being used to burn him. "No one talks about what goes on and you're not supposed to ever refer to it again." It is understood the incident happened 10 years ago.Reuse content