Nasir Khan (30) was nabbed by a joint team of police and 30th Assam Rifles personnel during the search operation at Irilbung area following reports of movement of some ultras yesterday.
During interrogation, Khan revealed that he joined the PULF about a year ago through his younger brother identified as Sahid Ahamed of the PULF, who was killed in an encounter with security personnel.
The militant also confessed that he was involved in extortion of money.