It is well known that cellular phones might be used for eavesdropping as bugging devices. Spy phones and remotely activated telephones can be easily hidden in high-security facilities like military headquarters, briefing rooms, banks, etc., where sensitive information is in jeopardy of being tapped. Using cell phone jammers neutralizes this threat. Once a cellular jammer is operating, all mobile phones present within the jamming coverage area are blocked, and cellular activity in the immediate surroundings (including incoming and outgoing calls, text messages, pictures and multimedia sending and receiving, etc.) is blocked.