Patna, Dec 10 (IANS) Five poachers, including a Nepalese national, were arrested in Bihar's only tiger reserve, officials said Wednesday.

Divisional forest officer Nand Kishor said that five poachers were arrested in the Valmiki Tiger Reserve (VTR) in the state's West Champaran district. Forest officials also recovered four heavy nets used to trap wild animals and birds.

The reserve is situated adjacent to the Indo-Nepal border.

"We suspect that the arrested poachers were planning to target wild animals in the VTR. They may have links with a gang of international smugglers selling exotic wild animals and birds outside the country," he said.

Kishor said after they were arrested, the forest division issued alerts to forest officials, including rangers and guards, to keep a close watch on activities within the VTR area. "We are not taking any chances as far as safety and protection are concerned," he said.

According to forest officials, poachers become more active during the winter season.

Last week, the forest officials had arrested three poachers who had trapped an elephant in the VTR area.

"We have been regularly recovering carcasses of animals in VTR, a clear-cut signal that poachers are active," a forest official said.

A few months back a tiger was found dead within the reserve. The Sashastra Seema Bal troopers deployed along the Indo-Nepal border had also recovered a consignment of animal body parts from inside the VTR.

Early this year the carcass of another tiger was found in the tiger reserve.

According to officials, there were 22 tigers in the reserve when last surveyed in 2013 using the camera trap method-based census. In 2010, the number of tigers was only 10.