Pehlu Khan, who was chased, beaten and kicked till he fell unconscious, died on Tuesday night.
On Saturday, the dairy farmer was returning to Haryana after buying cows at a Jaipur fair when he and his associates were attacked by a mob of around 200. They showed a Jaipur civic document as proof they had bought the cows for milk, but whether these were legit became irrelevant as the mob chased, kicked and punched them. The attackers bashed up their truck using roads and stones.
A local student leader is among four men arrested late last night after outrage over the perceived inaction of the state police. They were identified based on the videos that are viral online, the police said.
Right after the attack, 11 people were charged but all were survivors of the mob attack, accused of smuggling cows. Rajasthan is among the states that ban cow slaughter and also transporting of animals across state borders without a licence.
The government faced opposition anger in parliament, with the Congress alleging a "constitutional breakdown" in BJP-ruled Rajasthan.
There were similar protests in the Lok Sabha. Home Minister Rajnath Singh said, "The Rajasthan government is investigating and some people have been arrested. We will make all efforts to take action according to law."
Yesterday, Rajasthan home minister Gulab Chand Kataria told NDTV that both sides were to blame for the incident.
Rahul Gandhi, vice president of the opposition Congress party, tweeted: "When government abdicates responsibility and allows lynch mobs to rule, tragedies of immense proportion follow."