During the panchayat regime he was the general secretary of the underground leftist group Nepal Janabadi Morcha (NJM), living in exile in Lucknow, India.
After the 1985 Nepal bombings, which NJM had claimed responsibility for, Mayalu received a life sentence in absentia.
[citation needed] In the 1994 Nepalese legislative elections Mayalu was the candidate of NJM in the Dadeldhura constituency.
In total Maoists have seized 15 bighas (10.1 hectares or 25 acres) of land belonging to Mayalu.
[4] The 76-year-old former MP was receiving treatment for cancer at Bir Hospital, Mayalu's brother Chhabilal confirmed.