Security was beefed up in and around the Golden Temple in Amritsar on Thursday, a day after police received a letter, allegedly written by the outlawed Lashkar-e-Taiba, threatening to blow up the Sikh shrine.
The police have posted personnel in plainclothes around the temple. Over 150 ex-servicemen were deployed on security duties around the complex.
The SGPC has also beefed up internal security of the complex with its volunteers not allowing any bags and mobile phones inside.
District police chief Sudhanshu Srivastava said the letter was received at the office of the Shiromani Gurudwara Prabandhak Committee (SGPC) in the temple complex on Wednesday.
The SGPC handed over the letter, written in Hindi, to the police and filed a complaint.
The letter also mentioned that Hindu shrines Vaishno Devi and Raghunath temple in Jammu and Kashmir would be blown up.