In a widely-shared mobile video of the attack on Saturday, a mob chases and mercilessly beats five men. One of them, 55-year-old Pehlu Khan, died last night and his four associates are in hospital, badly wounded. One of the victims said the attackers "almost poured petrol on us and set us on fire".
Three vigilantes have been arrested by the police for the attack.
The minister said they have been charged with cow smuggling. He did not respond to reports that they had produced documents as proof that the cow in their truck was from a "Pashu Mela" or livestock fair in Jaipur.
He had earlier called the lynch mob Gau Bhakts (cow protectors). An FIR or police complaint says the attackers were from the Bajrang Dal and Vishwa Hindu Parishad, hardline groups which are linked to the RSS or Rashtriya Swayamsevak Sangh, the ideological mentor of the ruling BJP.
"It is a question of people's sentiment. And the law prohibits transporting cows for slaughter purposes. Which is why the general public is outraged with such incidents. Police stops these vehicles carrying cows and send the cow to gau-shalas (cow sheds). But no one can take the law into their hands, we have filed cases against both parties and will probe both cases," Mr Kataria said.