A 30-year-old alleged militant of Hizbul Mujahideen (HM), who the police claimed was on the run for the past 10 years, was arrested after a shootout at a park near the Indian Institute of Technology (IIT) on Sunday night.
The accused, identified as Mohammad Abdullah Chechi alias Abdullah Inquilabi, was wanted by the Jammu and Kashmir police in more than 12 cases including the killing of 25 Hindus in the Pir Panjal range.
Police said Inquilabi was trying to shift his base as he had fallen out with his sympathisers and bosses both in Pakistan and Jammu and Kashmir.
In the recent past Inquilabi had helped the police arrest some alleged HM militants by leaking information about their whereabouts, the police said.
On some occasions he had also double crossed the police and was responsible for the death of police personnel, the police added.
He was reportedly in Delhi for the past 20 days to set up a sleeper cell for future operations.
Inquilabi was known as "Mr Surrender" as he used to contact senior police officials with a proposal to surrender, the police said.
"Our team is in Delhi to interrogate Inquilabi," said Ashok Kumar, Inspector General, J&K police.
Police said Inquilabi, who came to Delhi on October 27, was not carrying any mobile phone and was continuously shifting base.
"During one of the interceptions, we heard Inquilabi giving directions to someone about his location. He was referring to an engineering college from where someone from his village had recently graduated. The person took the name of IIT Delhi and we swooped into action," said a senior police officer.
The police claimed Inquilabi was arrested after a shootout at Rose Park near IIT Delhi but no one in the vicinity had heard any gunshots.
There were no records of a police control room (PCR) calls either. The local police denied any knowledge about any shootout.
Police said Inquilabi was indoctrinated by a maulvi at age 19 and was later trained by a self styled leader of the disbanded Pira Panjal regiment-Masood Sarfaraz.
Police said he had stayed at various locations in east and west Delhi.
"We would be raiding his hideouts but it is not necessary whether these people were aware about his terrorist activities," said a senior police officer.
A joint team of intelligence bureau and military intelligence would be interrogating the accused.