A criminal investigation into alleged violent bullying rituals within the Royal Marines is the latest setback in Britain's armed forces' attempts to distance themselves from claims of abuse.
The British Ministry of Defence announced an urgent probe after a video emerged seemingly of a new recruit being beaten unconscious as part of an initiation ceremony.
Stills from the film, obtained by the News of the World, show the naked man forced to take part in a fistfight.
He is then apparently kicked in the face by another man, claimed to be one of his superiors in 42 Commando.
An MoD spokesman said: "The Royal Marines take these allegations extremely seriously and have a zero tolerance policy on bullying and harassment."
He said a probed by the Special Investigations Board (SIB) had been launched.
The video was covertly filmed by another marine who witnessed the fight in a field at 42 Commando's base in Bickleigh Barracks, near Plymouth, according to the newspaper.
Twelve new recruits who had just completed their 32-week Commando training are alleged to have taken part in the brutal initiation ritual in May, while around 40 other marines - also stripped naked - watched.
The images show two men in the centre of a large group.
At first they are apparently fighting with large mats rolled round their arms, but then another man dressed in a blue surgeon-style outfit steps and motions for a them to use bare fists.
When one of the recruits complains the man allegedly kicks him in the face, leaving him unconscious on the grass.