Two pickup vans were intercepted by a group of "cow protection unit" near Islampur village, 3 km from here, in the morning, said Savita Kataria -- the person who led the group.
Shathil Ahmad, a resident of Palwal district, and Tayaid were arrested and a search is on for two others who fled the spot, said Gurgaon police PRO Subhash Bokan.
According to Kataria, residents of the village went on a rampage after "they saw beef inside the vehicles" and thrashed Ahmad and Tayaid.
The police said the accused were on their way to deliver the beef consignment in Delhi, adding that the two vehicles had been seized.
"We have registered an FIR under various sections of the Haryana Gauvansh Sanrakshan and Gausamvardhan Act, 2015," the police added.
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