PATNA, Sept. 9 -- Patna police made tight security arrangements on Monday at Takht Sri Harimandir ji Patna Sahib after a threat mail received by it on Sunday claimed four RDX bombs had been planted on the gurudwara premises, police said on Monday.. Takhat sahib committee received an e-mail, in which the sender wrote that there were four RDX-based IEDs in the gurudwara's langar halls. "Immediately evacuate VVIPs and staff before the explosion," it said, the police added, quoting the e-mail. President of Takht Sri Harmandir Ji Management Committee Patna Sahib, Jagjot Singh Sohi said SSP K Sharma was immediately informed about the email. DSP, -2 Patna City Gaurav Kumar said the matter was being investigated The suspicious e-mail was being investigated by the cyber cell, he added. On August 29, a similar e-mail was sent to registrar of Patna civil court about planting RDX bombs at the civil court....