A 51-year-old New York dog breeder and his Bay State accomplice allegedly killed and tortured dogs in Lynn and disposed of them behind a gas station, prosecutors said.

Jason Gentry, 35, of Salem pleaded not guilty in Essex Superior Court yesterday to 12 counts of animal cruelty and one count of running an unlicensed kennel. Among the accusations is that he assisted in mutilating the dogs.

According to the indictment, Gentry “held the puppy during the cutting and/or cropping of the ears of the first of four puppies by means of scissors and duct tape, without the use of anesthetic, said puppy expiring at some point thereafter.”

Gentry’s lawyer, Ernest Stone, declined to speak following the arraignment. Gentry posted $1,500 bail and was released.

Dominick Donovan of Long Beach, N.Y., was arraigned in Superior Court Thursday on six counts of animal cruelty. He pleaded not guilty and posted $2,500 bail.

The dogs were found behind a gas station in Revere in November 2014. A necropsy determined the dogs — a female and a male — were about 20 weeks old and had been healthy when they were killed.

Both dogs had been in Gentry’s care at Alpha Canine Performance of Lynn, Suffolk prosecutors said. Donovan arrived there in November to transport the animals back to New York, prosecutors said. Gentry told police that on Nov. 2, the dogs were hung until they stopped breathing, prosecutors said.