Thieves used power tools to cut off the heads of three velociraptors at the National Dinosaur Museum in Nicholls on Saturday night.
CCTV footage showed the dinonappers arrive in a 4x4 dual cab ute shortly before 11pm before climbing a four foot fence to get to the dromaeosaurids.
The velociraptors, infamous for learning to open doors in the movie Jurassic Park, appeared to have been decapitated with angle grinders and a hacksaw, police say.
Police found the damaged raptors on Sunday, August 6 and appealed for witnesses to come forward.
Anyone with information or saw suspicious around the National Dinosaur Museum on Saturday night should contact Crime Stoppers on 1800 333 000 or via the ACT Crime Stoppers website.