"“In Mozambique we eat rats,” joked Alberto Augusto, the director of Mozambique’s national demining institute, “so it was very strange to see them working and demining. We were thinking to grill them.”

“These are not normal rats,” Augusto declared. “They are very special rats.”

The HeroRats are officially known as Mine Detection Rats (MDRs), specially trained by Apopo, a Belgian NGO that researches, develops and implements detection rat technology for humanitarian purposes like demining."
http://www.bbc.com/future/story/20130222-scratch-and-sniff-mine-detectors/1