Connecticut environmental officials said DNA tests on samples from seven animals in North Stonington showed that they are domestic dogs with no recent wolf ancestors.
The state responded to reports in March of hybrid wolfdogs attacking people and animals. Wolfdog hybrids are illegal in the state.
The Department of Energy and Environmental Protection said it's legal for the owner to have the dogs.
Environmental officials said that Ashbow Sebastian, the owner of the dogs, cooperated with the investigation. Officials said Sebastian, of North Stonington, agreed to allow DNA testing of the animals' saliva. Sebastian did not immediately return a call seeking comment.