Thieves apparently broke in at Rabindra Bhavan, which houses a museum where the Nobel Prize was on display. Besides that, there were numerous original documents which were also stolen.

The robbers broke open the glass case and escaped with the items. A lock of a glass case where the documents and the prize were secured were found broken.

They made away with several artefacts belonging to Tagore, including some gold medallions and rare paintings, police said.

"The stolen artefacts might also contain the Nobel Prize citation or the plaque," an official of Kolkata Police said.

Staff at Visvabharati University in Shantiniketan discovered the theft this morning.

University vice chancellor Sujit Basu is closeted with senior police officials over the robbery.

Forensic experts are already on the job. One of the main entrances to the university, Uttarayan Gate, has been shut.

"The police have cordoned off the entire area. They are not allowing in even the Viswa Bharati staff," the spokesman said, confirming that the plaque stolen was the original one.

Chief Minister Buddhadeb Bhattacharjee said that a CID team had been rushed to Viswa Bharati to conduct the investigation.