London - MI5 was yesterday strongly criticised by a parliamentary committee overseeing the intelligence agencies because of the failure to prosecute Ms Melita Norwood. The Intelligence and Security Committee said Ms Norwood (87) - who was publicly unmasked as a KGB spy last year - escaped prosecution because a junior MI5 officer decided the case was not worth pursuing. In its report on the affair, the committee said it was a "serious failure" on the part of MI5 not to refer her case to the government's law officers, given the scale of her alleged treachery.