A special investigation team set up on Wednesday to probe the disappearance of a student of RG Kar Medical College and Hospital is yet to make any headway.

The team was formed on orders from chief minister Mamata Banerjee after family members of Avijit Singh, a second-year MBBS student, called on her at Nabanna.

Avijit, from Bihar's Muzaffarpur, has been missing since leaving his hostel on Indra Biswas Road in Belgachhia, a 5-minute walk from the campus, on Saturday afternoon.

The SIT - headed by Sujit Mitra, deputy commissioner in charge of special branch-II - has collected the call details of Singh's two cell phones from the service providers.

"The numbers Avijit had dialled and from which he had received calls before his disappearance are under our scanner. We will trace the persons in whose names the numbers have been registered and will talk to them," a senior police officer said.

A six-member team of doctors formed by the medical college to look into the disappearance has drawn a blank, too.

Singh was last seen leaving the hostel in shorts and a T-shirt around 12.30pm on Saturday, leaving behind his two cell phones, wallet, finger rings and a gold chain. His disappearance was noticed around 9pm when dinner was about to be served.