Four poachers have been arrested in West Bengal's Alipurduar district for keeping a rhinoceros horn and illegal arms, wildlife officials said on Wednesday.Acting on a tip, Jaldapara Wildlife Sanctuary officials raided the house of prime accused Sanjay Rava in Mindabari on Tuesday afternoon and arrested him."We have recovered a rhinoceros horn and an AK-47 with 46 cartridges from Sanjay's house," Divisional Forest Officer Bhaskar J.V. said."Three more poachers, including Lachu Rava and Arjun Rava, were also arrested from Sanjay's house. They helped him in poaching and supplying wildlife objects," he said.According to the Forest Ministry, over 150 poachers have been arrested since 2014 for poaching, smuggling and supplying wild animals and wildlife objects from different sanctuaries in West Bengal.