The Radio Times has issued an apology after inadvertently giving more exposure than intended to the Royal Marines.

A photograph in this week's issue of the magazine shows members of 42 Commando - one of whom is actually going commando.

The article, to promote Channel 5 documentary Royal Marines: Mission Afghanistan, was printed before the unidentified marine's prank was spotted. The series intends to lay bare the truth about life in the military.

Staff at the Radio Times only noticed the privates-on-parade blooper when a reader wrote in today.

The reader said: "I know that British soldiers serving in Afghanistan are well equipped, but seeing the roll call of Royal Marines gives the expression a whole new meaning."

The magazine swiftly dealt with the fall-out by printing an apology on its website, alongside a censored version of the photograph showing a red x over the offending area.

Editor Ben Preston said: "We apologise for any upset caused to readers by the rogue member of 42 Commando."

A spokeswoman for the Radio Times added: "The unnamed marine is, like the rest of his unit, posing for the photograph dressed only in shorts.

"What we took to be the marine's finger proved, on closer inspection, to be another part of his anatomy."

The 28 January issue of the magazine went on sale today.