A director of a private security agency is being quizzed by the intelligence bureau and army sleuths after he was arrested with three walkie-talkie sets that could let him eavesdrop on messages transmitted over the police wireless network. Waqar Khan, who runs a private agency Defence Security Service Private Ltd., was arrested on Saturday following a tip-off that his walkie-talkie sets were programmed to the frequency and bandwidth of the police wireless network thus enabling him to eavesdrop on police messages.