A high-security alert has been declared in Nagpur, Maharashtra, India, after an anonymous letter claimed that radioactive material was planted at significant locations, including the Rashtriya Swayamsevak Sangh (RSS) headquarters and a Bharatiya Janata Party (BJP) office. The letter, received by Police Commissioner Dr. Ravinder Singal on April 27, was written in English and allegedly sent by a group identifying itself as 'DSS'. It contained alarming claims about Caesium-137, a highly radioactive substance, being placed in various locations, including under seats of Metro trains on the Orange and Aqua lines and on 'Aapli Bus' services. Police and the National Disaster Response Force (NDRF) have conducted thorough searches but found no radioactive material, leading them to suspect the letter may be a hoax. However, security has been intensified around sensitive locations, and efforts are ongoing to trace the letter's origin and identify the individuals behind the threat. A case has been registered at the Sadar police station, and the Anti-Terrorism Squad (ATS) is involved in the investigation.