The man allegedly made the call to the local police control room in the morning and claimed that a bomb was kept inside the ivory-white marble mausoleum in the northern Indian state of Uttar Pradesh's historic city of Agra, some 250 kms from the national capital.

Immediately, the para-military Central Industrial Security Force that protects the 17th-century monument swung into action and evacuated some 1,000 visitors on the pretext of a search operation because of a sudden VVIP visit.

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"A search, involving sniffer dogs, was carried out by the para-military personnel for nearly two hour before the Taj Mahal was again thrown open for visitors," A Satish Ganesh, a senior officer of Uttar Pradesh Police, told the media.

“Nothing objectionable was found inside the Taj Mahal premises in the search and thus the call about a bomb threat in Taj Mahal was deemed to be a hoax call,” he said.

Police said a man was detained for questioning within hours of the call. "Prima facie, it seems that he is mentally unstable and undergoing treatment. But we are trying to find out why he made the hoax bomb call," Satish said.

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The Taj Mahal was commissioned in 1632 by then Mughal emperor Shah Jahan to house the tomb of his favourite wife, Mumtaz Mahal. The monument, built by 20,000 artisans, also houses the tomb of Shah Jahan himself.

The Taj Mahal complex is believed to have been completed in its entirety in 1653 at a cost estimated at the time to be around 32 million rupees, which in 2020 would be approximately 70 billion rupees (about USD 956 million.

The monument attracts 7–8 million visitors a year and in 2007, it was declared a winner of the New 7 Wonders of the World initiative.