Concerns were raised in internal LAS documents over the performance of radios and communication equipment used in the emergency operations after the 7/7 attacks . Again , the sheer volume of emergency calls received made radio communications difficult and put pressure on staff in the ambulance control room . Staff were also hampered in their use of mobile phones as the mobile phone networks were temporarily brought down during the day . In July 2009 the new radio system recommended after the bombings was rolled out
7/7 attacks
7 July 2005 London bombings
London Ambulance Service