RJD leaders were seen joining the protest by the Left parties.
The Left parties on Tuesday staged a protest at Parliament premises, accusing the BJP government in Tripura and the Trinamool Congress government in West Bengal of "murdering" democracy and violating human rights in the two states.
Lawmakers of the Left parties alleged that there has been an increasing number of incidents in the two states where human rights and political freedom of people have come under severe threat.
"The change of regime in both states has been accompanied by an unprecedented, sustained violence and attacks in all spheres against the members and supporters of the Left parties. In Tripura, it is the BJP-RSS combine which is leading the attacks on the Left and in Bengal it is the TMC which is unleashing the violence," CPI(M) leader Mohammed Salim told reporters.
The Trinamool Congress also staged a sit-in at the same time in front of the Mahatma Gandhi statue in Parliament premises accusing the BJP of patronising the culprits behind the incidents of lynching across the country.
Both the protesters of the Left parties and Trinamool were seen facing each other while shouting slogans just before the start of the session on Tuesday.
TMC leader Derek O'Brien alleged, "The BJP government is behind incidents of lynching all over the country.
"Prime Minister Narendra Modi should tell us why these incidents are happening. They are trying to divide India. Stop lynching. Stop politics of hatred. We are for an united India," he said.
Interestingly, while the Telugu Desam Party joined the protest of TMC, RJD leaders were seen joining the protest by the Left parties.
Later, both the Left and Trinamool lawmakers took up their issues during the zero hour in the Lok Sabha.