BAYSIDE, Queens—In a slick shell game, a quick moving thief made off with a 100-year-old tortoise at Alley Pond Environmental Center, police sources said.

The ​”rare” tortoise w​as​ discovered missing from ​its enclosure​​​ around 4:15 p.m, by the center’s head of operations, sources said.

The​ fenced in enclosure appeared to be forced open and detectives were searching for surveillance video, sources said.