Bhubaneswar, May 13: Police today detained state president of National Students' Union of India (NSUI) Itish Kumar Pradhan and his supporters when they tried to barge into Naveen Niwas, the official residence of chief minister Naveen Patnaik.

The members of the student wing of the Congress staged a demonstration demanding a CBI probe into the death of an engineering student on May 6 last year, alleging involvement of mayor Ananta Narayan Jena in the incident. "We decided to stage the demonstration today as it was the birth anniversary of the deceased student. We have been demanding a thorough probe into the incident but the police have been shielding a politician of the ruling party. There should be a CBI probe to unearth the mystery behind his death. On May 25, students will gherao the chief minister's residence," said Itish.

While the police have been claiming that the student died of drug overdose, several political parties, including the NSUI, alleged involvement of mayor Jena in the death of the 23-year-old student. NSUI members also demanded action for their detention by the cops.

"The area around the residence of the chief minister is a prohibited area and according to the rule, five people are not allowed there. There were only four of us. We were peacefully going to the Naveen Niwas to discuss the progress of the case with the chief minister. But, the police detained us forcefully," Itish said.

Friends of the deceased had also claimed that a controversial sex tape, which allegedly featured Jena, had a connection with his death. The incident had led to widespread agitation by various political parties demanding resignation of Jena. In December, the Janpath had turned into a battle zone after the members of BJP and BJD clashed several times during a bandh called by the BJP demanding resignation of Jena. About, 20 people from both the groups were injured during the clash.

Deputy commissioner of police Satyabrata Bhoi said that the investigation in the case is still under way. "We have sent the mobile phone of the deceased to the Central Forensic Science Laboratory in Calcutta as it was locked. We are waiting for the report," Bhoi said.