Tingraj Orang, a top Maoist in Assam has surrendered himself in Guwahati on Tuesday.

Orang was in-charge of expanding the base of proscribed outfit CPI (Maoist) in Brahmaputra and Barak valleys. He surrendered himself before Additional Director General of Police, Special Branch, Hiren Nath.

The 49-year-old Maoist was the convener of the outfit's Assam State Organising Committee (ASOC) and also the general secretary of its Barak and Brahmaputra valley zonal committees.

Orang's surrender is considered a major setback for CPI (Maoist) in Assam and the ASOC would also become leaderless.

He hails from Samuktola village in Dibrugarh district.

Orang joined the CPI (Maoist) in 2006. He was also associated with SFI and CPI (M) from 1989 to 1999.

Earlier in 2011, Orang along with two other Maoists were arrested in Odisha's Rourkela but subsequently released.