Guwahati, Feb. 20: An alleged confession made by Ulfa (I) cadre Gagan Hazarika alias Joydeep Cheleng has helped the National Investigation Agency (NIA) to corroborate that the rebel outfit's chairman Abhizeet Asom is UK-based doctor Mukul Hazarika.

An official source today said Gagan had told the NIA during interrogation that he had served as the bodyguard of Abhizeet Asom during his visit to Ulfa (I) camp in Myanmar after he became the outfit's chairman in 2012.

"Since Gagan was the personal bodyguard of Abhizeet Asom, he was closely associated with him during his stay at the outfit's Myanmar camps and, therefore, his revelation that Mukul Hazarika is Abhizeet Asom will be useful evidence for the NIA to establish the real identity of Ulfa (I) chairman and push for his extradition," the source said.

The anti-terror agency has also collected photographs of Dr Hazarika visiting Ulfa (I) camps in Myanmar and meetings senior leaders of other militant groups.

The source said the NIA would soon move the court for issuing an arrest warrant against Dr Hazarika as a prelude to requesting the UK for his extradition.

Gagan, who joined Ulfa in 2008, was arrested from Charaipung police station area in Upper Assam's Charaideo district last month. He was arrested by the NIA in connection with case number 4/2013 registered at its Guwahati office regarding illegal and anti-national activities of Ulfa (I).

Ulfa (I) has denied that Mukul Hazarika and Abhizeet Asom alias Abhizeet Barman are the same person.

The source said apart from being a practising doctor in the UK, Hazarika was associated with the UK-based human rights group, Assam Watch, which used to raise alleged incidents of human rights violation by security forces in the state.

He said Assam Watch is an alleged front of Ulfa, which had arranged the travel of then Ulfa chairman Arabinda Rajkhowa and general secretary Anup Chetia to Geneva to attend a meeting of the UN Sub-Commission's Working Group on Indigenous People in July 1997.

He said Dr Hazarika, who is in his late sixties, hails from Kaxori gaon in the Puranigudam area under Samaguri police station in central Assam's Nagaon district, about 120km from here. He studied at Radha Kanta Baruah Higher Secondary School in Puranigudam from 1955 to 1962 where his father, late Kameswar Hazarika, was the headmaster.

"He completed his MBBS from Gauhati Medical College in 1970 and left for the UK around 30 years ago. His relatives in his ancestral village said the last time he came to Assam was for a few days in 1983 when his father expired and after that they had neither seen him nor had any contact with him," the source said.

He added that the school had come under the NIA scanner in 2015, after Dr Hazarika sent two table-tennis platforms to his alma mater, as the agency had information that Dr Hazarika could be Abhizeet Asom.

A British site on the country's doctors, http://www.doctoralia.co.uk/consultant, lists Mukul Hazarika as a general practitioner at Billingham town in Durham.