British troops have been placed under criminal investigation over the detention more than 13 years ago of Iraqis suspected of murdering two Army soldiers, The Telegraph can disclose.

The servicemen have been investigated in secret for more than two years over the alleged ill treatment of the two Iraqis accused of carrying out one of the bloodiest and most notorious attacks on British troops during the conflict.

The soldiers face prosecution and, if found guilty, possible jail terms.

Military chiefs have branded the criminal inquiry into the troops an outrage and a betrayal of the Armed Forces.