Ten people had been held till now related to Madan's murder case.
Nikal Tamang is the member of Central Committte of Gorka Janmukti Morcha (GJM).
His mobile was detected from the murder site.
According to CNN-IBN, the FIRs was registered against 23 people including the GJM President Bimal Gurung.
The GJM was also accused of involvement in Madan Tamang's killing.
Gorkha leader Madan Tamang was murdered in Darjeeling on May 21, 2010.