The US Department of Homeland Security introduced a special plan - known as Standing Operating Procedure 303 - to block signals of cellular operators after cellular phones were used to detonate explosive devices during the bombings of the London subway system, Pravda.Ru reports. A federal appeals court wants to know why the government should be allowed to keep secret its plan to block cellular communication for the time of "critical emergencies." Standing Operating Procedure 303 is a powerful tool in the digital age ... The US Court of Appeals for the District of Columbia Circuit in February sided (PDF) with...