The "Mine Turtles", Nicknamed by Dr.Ska, are approcximately 156 specimens of family, Trachemys scripta elegans, or Red-Eared Sliders.
However, the only difference is that these turtles have landmines embedded into their shell. These turtles are born with the mines in their shells.
Any new specimens are to be studied, and either terminated or put back into containment. In the event they escape, all employees are advised to watch their step.
These turtles were found in Northern Florida, 1946. Any reported specimens are to immediately be investigated, and terminated.
Upon detonation of their shell-mine, the turtles will be completely unaffected, as their shell is seemingly invulnerable to explosions.
Research into their shells being used as bullet-proof material is currently ongoing.
Addition : Upon recent discovery, it appears these turtles have been a common species since before Humanity walked the earth. It is unknown why their "Mines" are so similar to man-made land-mines.