Lucknow, Jan 26 (IANS): An IIT-Kanpur graduate, currently pursuing an MBA from IIM-Lucknow, has been taken into custody by the CBI as a key suspect in the killing of his friend Aadesh Bajpai who went missing over three years ago.

Central Bureau of Investigation (CBI) sleuths zeroed in on 28-year old Rahul Verma after running a wild goose chase for almost one year when the case was entrusted to the agency by an order of the Allahabad High Court. He was arrested Wednesday evening.

"Rahul was tracked down on the basis of sufficient circumstantial evidence as he was the last person whom Aadesh visited before he vanished Aug 10, 2008," a CBI source said.

Calls exchanged between Rahul and Aadesh on that day were also traced by the CBI. Their meeting on the fateful day was also corroborated by Aadesh's Kanpur-based relative Vivek Trivedi, whom he had told that he was going to meet "a friend" at IIT-Kanpur.

Earlier investigations had revealed that Rahul and Aadesh had come in contact through a social networking site for gays. A fashion designer by profession, Aadesh was working in a Mumbai-based company.

Aadesh's parents came down to Kanpur a few days after he went missing.

About two weeks later, policemen discovered a skull and bones from a gunny-bag, thrown in a ditch behind the faculty residential quarters. The bones were stated to be the remains of a human body apparently burnt with acid.

The police sent the bones for forensic examination but the DNA match with Aadesh's father turned out to be negative, following which the case was transferred to the Criminal Investigation Department (CID).

However, following appeals by the victim's parents, who sought intervention of the Allahabad High Court, the case was entrusted to the CBI towards the end of 2010.

The CBI got another forensic test done which revealed that the bones belonged to Aadesh.

"Initially, it seemed like an open and shut case but all clues were leading us to Rahul who had earlier been under the police scanner but could not be arrested because there was no direct evidence against him," a CBI official said.

"We therefore decided to arrest him, and now that the court has accepted our application for remanding him to CBI custody, we hope to crack the case soon," he added.