The animal was spotted at Mandawar village here in the morning. It was seen attacking a few stray animals, Rambir Singh, Conservator of Wildlife, Gurgaon said.
Soon, a huge crowd of nearly 1,500 people from nearby Kasan ki Dhani and Sukhroli villages gathered and started attacking the animal with axes, bamboo sticks and stones, he said.
In the melee, nine persons including a guard of the Wildlife Department were injured, the official said.
Meanwhile, irate villagers complained that the forest officials reached the venue late.
"We informed the forest department and Gurgaon police immediately after spotting the feline. However, they reached the spot late," a villager Dhani Ram said.
Singh, however, said that a team of district forest officer, three inspectors and veterinary doctors reached the spot within half an hour with all safety measures and a cage to catch the leopard.
"We faced difficulty when an aggressive mob of around 1,500 villagers started attacking the leopard. The animal also retaliated and in the scuffle, nine persons were injured. The leopard died later," he said.
The Wildlife Conservator said legal action would be taken against those responsible for the death.
"We will take legal action against those found guilty of killing the animal. A panel of three doctors has been formed to do the postmortem," he said.
Singh added that the entire incident was videographed and the matter has been reported to Gurgaon Police Commissioner.