DAY 6 - Mon 4 NovBy Martin HickmanSecurity guards working for News International used codewords from war films and the Cold War during a covert operation to hide evidence from the police, the Old Bailey heard today.Andrew Edis, prosecuting, read out text messages between the security guards while claiming that Rebekah Brooks, her husband Charlie and News International's head of security, Mark Hanna, plotted to conceal evidence from police prior to her arrest in July 2011.On July 17 2011, he told the jury, computers and other material were removed from the home of the Brookses and hidden - probably behind some bins, he said - at their home in Chelsea Harbour, London. The computers were later found and handed to the police.One of the messages read: "Broadsword to Danny Boy. Pizza's delivered and the chicken is in the pot." According to Mr Edis, "Broadsword to Danny Boy" was the codeword used by Richard Burton's character in the Second World War film Where Eagles Dare.Another message - shown on a screen to the jury - suggested that one of the guards thought they should have used a "DLB" - or dead letter box, a technique used by Cold War spies.Mr Edis said the Crown's case was not that the computers contained "devastating evidence of phone hacking" but that "the only rational explanation for it [the alleged stowing of the material] was that it was designed to hide material so the police didn't get it."Mrs Brooks and her personal assistant are separately accused of trying to pervert the course of justice by removing seven boxes of her journalistic notebooks from News International's archive on 8 July 2011. The notebooks have never been found, Mr Edis told the jury.Earlier this morning, he told the court that Mrs Brooks had taken an active interest in the deletion of emails at News International covering the period of phone hacking.He read out an email by her in July 2010 setting the date before which all emails should be destroyed. It read: "Yes to jan 2010. Clean sweep."All defendants deny the charges. The case continues.