Apopo is a Belgian NGO with its registered office in Tanzania that studies the possibilities offered by the training of African giant rats to search for anti-personnel mines and identify tuberculosis outbreaks. The giant African rats, coming from the sub-Saharan region, are more similar to large rodents and can reach up to 90 cm and weigh up to 2.8 kg and have highly developed hearing and smell. These rats are very intelligent animals especially when trained at a young age and are preferred to dogs for their lighter weight, exerting less pressure when walking over mines. Through click / reward training the "Hero Rats" are taught to scratch the earth over a mine, at this point they hear a click and are rewarded with food. Unlike metal detectors, mine detection rats (MDRs) are trained to ignore the debris and only smell the explosive which makes them effective and very fast mine detectors compared to humans. Apopo still operates in Cambodia, Angola, Mozambique, Colombia, Zimbabwe, Vietnam, Laos and Thailand.