The locals ganged up, encircled the tiger cub and beat it to death. The 6ft 4inch long cub was only two years and four months old, local forest official Mahmudul Hassan said.
The incident took place at Gulishakhali village in Nishanbarhi union on Tuesday, according to Union Parishad Chairman Abdur Rahim Bachchu.
The villagers said a number of people at Gulishakhali village were injured in the attack by the tiger. They were being treated at the Khulna Medical College hospital.
Rahim said five others were also injured in the attack.
Later, the forest guards at Gulishakhali camp and the villagers beat the tiger to death, he said.
"I heard that a tiger has been killed by the villagers after they were attacked. The forest department workers brought the dead tiger to Mongla Animal Resource office for autopsy," forestry official Mahmudul said.
A five-strong investigation committee has been formed with Assistant Forest Reserve Officer of Sundarbans (North) Sadar Range Mehdi Zaman as its head to look into the incident.
The Wild Life (Preservation) Act stipulates maximum seven years of prison term and also Tk 1 million in fines for killing tiger and elephant. The law, however, exempts killing in self-defence.