Seven Sumatran rhinos have been captured on hidden cameras in an Indonesian national park where the critically endangered species was feared extinct, a conservationist said Thursday. The Sumatran rhino had not been sighted in the Mount Leuser National Park on the northern tip of Sumatra for 26 years, the project\'s team leader Tarmizi of the Leuser International Foundation said. \"This discovery can allay doubts over the rhino\'s presence in the park,\" Tarmizi told AFP, adding he hoped the discovery would encourage more efforts to conserve the species. Images of the rhinos were captured by 28 infrared cameras set up between June 2011 and April this year and confirmed six female and one male rhino appearing in 1,000 photo frames. The Sumatran rhino population has dropped 50 percent over the past 20 years, and there are now believed to be fewer than 200 left in the world. The rhinos are commonly targeted by poachers and rampant illegal logging has destroyed much of their habitat.