Six suspected tiger poachers were killed Sunday evening during a gunbattle with Bangladesh police in the Sundarbans, the world’s largest mangrove forest. Five police officers were also injured in the incident, authorities said.

The incident occurred in the Koyra area of Khulna district, about 197 miles southwest of the country’s capital of Dhaka. Police seized four guns, three pistols and skins of three adult tigers from the suspects. A major part of the Sundarbans wildlife reserve, home to the endangered Royal Bengal tiger, stretches from the eastern coastline of India across the international border.

“Police initially detained six of the poachers and asked them to lead us to their hideouts inside the forest ... Their associates attacked us and we retaliated when the six were killed in crossfire,” a police officer said, according to Press Trust of India (PTI) news agency.

Poaching is the main reason for the decline in the numbers of the Royal Bengal tiger and, in June, a survey found that the population of the tigers on the Bangladesh side of the Sundarbans dropped drastically to 106 this year, down from 440 in 2004. About 40 percent of the Sundarbans lies in India, which is home to about 74 tigers, PTI reported.

Primarily found in India with small populations in Bangladesh, Nepal, Bhutan, China and Myanmar, the population of these tigers remains fewer than 2,500 in the wild.

"The threat comes not only from stray poaching, which is rampant, but also from organized gangs of poachers. Unless we have an independent, dedicated anti-poaching unit, the future is not bright for the tigers in Bangladesh," Anwarul Islam, professor of zoology at Dhaka University, told BBC in June.