The violence began on Friday when protesters belonging to the Gujjar community lynched a policeman in the state of Rajasthan. Police later opened fire on rioters, killing 36 of them in subsequent days.
The Gujjars, already considered a disadvantaged group, want to be reclassified further down the complex Hindu caste and status system so they qualify for government jobs and university seats reserved for such groups.
Police said hundreds of Gujjar protesters paralysed traffic, squatting on rail tracks and a highway connecting Jaipur, the state capital, to the Taj Mahal town of Agra, as well to India's financial capital Mumbai.
The army and paramilitary forces patrolled the Gujjar-dominated areas, which continued to report stray incidents of protesters burning tyres and damaging vehicles.
"Almost all the national highways are functional except for Jaipur-Agra where a 20-30km of diversion has been made", V.S. Singh, Rajasthan's Home Secretary, told Reuters.
Indian media reported on Tuesday that food supplies to the Gujjar-dominated areas had been cut, but Singh denied this.
Gujjars say they deserve preferential treatment, but a state government committee did not agree, and announced instead it would spend INR2.8 billion (Dh246 million) improving schools, clinics, roads and other infrastructure in Gujjar areas.
The Rajasthan government has warned the protesters to back down or face further police action.
"They should stop testing our patience," G.C. Kataria, Rajasthan's home minister, said. "Otherwise the authorities would be forced to throw them out and very many lives could be lost."
On Tuesday, a Rajasthan court asked the protest leader, K.S. Bainsla, to appear before it for failing to stop his community members from breaking the law. Separately, police filed murder charges against Bainsla for the lynching of the policeman.
A year ago, Gujjars in Rajasthan fought police and members of another caste that already qualifies for job quotas. At least 26 people were killed in that violence.