Santiniketan, April 4: The plot to steal Rabindranath Tagore’s Nobel medal and other treasures from the memorial museum at Visva-Bharati was chalked out in an abandoned guesthouse, CBI sleuths said today.

The thieves spent a few minutes in the veranda of the SAIL guesthouse, yards from the scene of theft, before sneaking into the premises of Uttarayan, the complex that houses the Rabindra Bhavan museum.

Officials said the location of the guesthouse, partially covered by bushes and trees, was perfect for planning a crime.

“During examination of local people, we came to know that no one normally enters the guesthouse premises. But, we have found evidence in the veranda that there had been an assembly there recently,” said the official.

During a search carried out by senior CBI officials led by joint director Vivek Dubey and experts from Central Forensic Science Laboratory, three empty beer bottles were found on the premises.

“It appears there were three of them and they spent a few hours before entering Uttarayan. They may have held a number of meetings at the guesthouse before the strike,” said a CBI official.

The sleuths have also come to know that one or two of the culprits were pan masala addicts. “It was a particular brand and we found small empty pouches of it from several places on the Uttarayan premises and outside,” said an official, adding: “It seems, after committing the crime the criminals took a lane leading to the Santiniketan-Shyambati Road that runs past the guesthouse.”

The CBI officials also found that the tools used to unlock the museum window and for cutting the wire fencing were the same. “But it was the act of an expert. They cut the fencing neatly. The opening of the window was also a noiseless-operation,” the official said.

To find out whether an insider was involved in the theft, the CBI has begun an extensive interrogation of the National Volunteer Force personnel who are in charge of guarding Santiniketan along with Visva-Bharati’s own security people.

The sleuths questioned the voluntary force members till Saturday midnight at the museum office.

This morning, the CBI officials summoned volunteer force guard Kartik Mahato and questioned him through the day. Three others — Nepal Das, Anandagopal Singh and Debojyoti Ghosh — were also summoned to the office. “These three used to guard the museum two years ago. We examined them to clear some points related to our examination,” said a CBI official. Officials also interrogated employees handling the airconditioning plant of Kala Bhavan.