Harare - An ivory poacher was killed in a shootout with police in northern Zimbabwe, a conservation group has said.Ten tusks were recovered in the operation on the Matusadona side of Lake Kariba, a day after another shootout between poachers and rangers elsewhere in the Zambezi Valley.In the latest incident on Tuesday night, a gang of poachers attacked law enforcement agents who surprised the alleged poachers as they tried to sell tusks, said the Matusadona Anti-Poaching Project (MAPP) in a post to Facebook.One poacher tried to stab one of the arresting officers while another poacher opened fire, MAPP said.The Black Mambas, as the anti-poaching team was called, killed one poacher and recovered 10 tusks.No one was killed in the first shootout, which reportedly happened on Monday.Conservationists in the area said they were two separate incidents. Poisoned with cyanide"It's happening all the time," a source told News24.Elephant populations in the Zambezi Valley were reportedly down by 40% at the end of 2014 because of poaching. In the Matusadona area, south of the lake, the population was reported to have dropped by 75% over a 13-year period.The Zimbabwe authorities were stepping up their fight against the poaching of elephant, rhino and other game, handing down some heavy sentences to convicted poachers. Around 60 elephants were poisoned with cyanide in north-western Hwange last year. Poachers took some, but not all of the tusks.The carcass of another poisoned elephant was found in a forest next to Hwange National Park, it was reported on Sunday.In a separate case, there was some disappointment in online forums over a magistrate's decision on Monday to grant $100 bail to the alleged ringleader of a rhino poaching gang in southern Zimbabwe. Munashe Murwira, a senior member of the Central Intelligence Organisation, was allegedly behind the killings of four rhino in the Save Valley Conservancy and involved in a shoot-out with detectives at the end of last year.His case would continue on March 4, the state-owned Chronicle newspaper reported earlier this week.