We have murdered!!!!

This morning when we opened our door to go to the office, a little gecko ran into the living room. Tim ran and grabbed it by the tail to throw it back out and it's tail came off!!!!!!!!!!!!!!!!! It frightened him and he dropped the tail. It kept wiggling all over the floor. The gecko was stunned a little and then ran under the sofa. We moved the sofa and there it was- we think dead. It didn't move. We looked back and the tail was still wiggling. Creepy!