The Taj Mahal complex in Agra was vacated on Thursday morning following a hoax bomb call, police said.
The caller, identified as Vimal Kumar Singh, has been detained for questioning in Firozabad, Additional Director General of Police, Agra zone, A Satish Ganesh said
Singh called the 112 emergency response number of the Uttar Pradesh police at around 9 am and claimed that a bomb was kept inside the monument that is conserved by the Archaeological Survey of India and protected by armed personnel of the Central Industrial Security Force.
The police immediately informed the CISF personnel, who asked the visitors to vacate the premises of the iconic 17th-century monument and launched anti-sabotage checks around 9:15 am.
Nothing suspicious was found during the checks at the monument, a CISF officer said in Delhi.
An initial probe revealed that Singh is a resident of Patiyali in Kasganj and was presently staying in his maternal grandmother's house in Okhra village in the Narkhi area of Firozabad, the ADG said.
"Prima facie it seems that he (Singh) is mentally unstable and is probably under treatment. We are probing why he made such a call. The Taj Mahal was reopened for visitors after about an hour and 45 minutes," he added.