Thirteen Left-wing extremists, who were accomplices of veteran CPI(Maoist) leader Arun Kumar Bhattacharjee alias 'Kanchan Da' arrested earlier this year, have surrendered in Dibrugarh and Cachar districts of Assam, a top police officer said.

"13 cadres of proscribed CPI-M joined mainstream today - leaving the path of violence behind - at Dibrugarh and Cachar. They are associates of CPI-M leader Aru Kumar Bhattacharjee @ Kanchan da who was arrested earlier this year by @assampolice," Special Director General of Police, GP Singh said in a Tweet on Thursday.