Vijay Sampla has also sought a report from Haryana police into the incident.
A day after the gruesome killing of a man at Delhi's Singhu border, National Commission for Scheduled Caste Chairperson Vijay Sampla on Saturday said the farmer leaders cannot "wash their hands off" the incident.
Speaking to reporters, Mr Sampla said whatever incident happens at the protest site, farmer leaders are responsible for it.
"Their role is the same as that of culprits. They cannot wash their hands off the incident," he said.
Mr Sampla made the comments after meeting around 15 Dalit outfits who submitted a memorandum to the National Commission for Scheduled Caste on Saturday demanding stringent action against those who killed the man.
Mr Sampla has also sought a report from Haryana police into the incident.
Mr Sampla said the man identified as Lakhbir Singh is from Scheduled Caste community.
The body of Lakhbir Singh, a labourer from Punjab's Tarn Taran district, was found on Friday tied to a barricade at the Singhu border with a hand chopped off and multiple wounds caused by sharp-edged weapons, the incident being blamed on a group of Nihangs.
Sarabjit Singh, arrested on Friday for the brutal killing, was produced before a Sonepat court in Haryana and remanded in police custody for seven days.
Hours later, Narain Singh was also arrested by the Amritsar Rural police at Amarkot village near Jandiala Guru in Amritsar district, the police said.
In a video clip that had gone viral after the incident, some Nihangs are seen standing as the man lies on the ground in a pool of blood with his chopped off left hand lying next to him.
The Nihangs are heard in the clip saying the man has been punished for desecrating a holy book of the Sikhs.
The Samyukta Kisan Morcha (SKM), an umbrella body of farmer unions that is spearheading the protests at Delhi's borders against three agriculture laws of the Centre, had on Friday said a group of Nihangs had claimed responsibility for the brutal killing after the man allegedly attempted to desecrate the Sarbloh Granth, a holy book of the Sikhs.
The SKM had also issued a statement on Friday distancing itself from the incident and said that it wanted to make it clear that "both the parties to the incident", the Nihang group and the victim, have no relation with the Morcha.