The son of a former Randolph AFB colonel was ordered to serve eight years in prison Thursday after a daylong sentencing hearing in which he admitted to the mutilation of three cats he got from Craigslist ads.

Austin George Patterson, 21, cried frequently as family members described mental issues that started in his teens and begged state District Judge Sid Harle to give him probation.

Harle agreed with family members that since his arrest in 2007 for animal cruelty and his subsequent stay at a mental hospital, Patterson has done everything right to become a productive member of society.

“But I've got to consider, frankly, the message,” he said, acknowledging the national attention — including an article in the National Inquirer — that Patterson's case generated.

Patterson was arrested after investigators found his vehicle near Cibolo Creek Trails, where a pedestrian had discovered the carcasses of three gray tabbies that were duct taped in the shape of a triangle to a piece of plywood. Two had slit throats and the other had been disemboweled.

A box containing knives, scissors, a hammer and nails also was found nearby.

Patterson said Thursday that he had fallen into deep depression because of bipolar disorder and was obsessed with “all things horror.” He described in a soft-spoken voice two other killings, one in which he tied a cat to a tree and burned it alive.

“The irony of all this is that I'm an animal lover, and that includes cats,” he said. “For the rest of my life, as long as I live, this will be something I look back and hate myself for. I was a deeply troubled, mixed-up person.”

Besides the bi-polar disorder, Patterson had a psychosis in which he was hearing voices from a presence he called “the wolf,” said defense attorney Andrew Del Cueto. But since getting treatment, he's become a new person, Del Cueto said.

Prosecutor Bill Pennington pointed to the more than 500 letters the district attorney's office has received from across the country expressing outrage about the cat deaths.

“He was able to convince two families to give up their animals that they love,” Pennington said. “He was manipulative.”

Retired Col. Greg Patterson, the defendant's father, and former police officer George Patterson, his uncle, both wept as they recalled Patterson falling into a dark, aloof, antisocial cloud for years leading up to his arrest.

“He was into heavy metal, black clothes, nunchucks,” his uncle said.

But he's always been small, lanky and soft-spoken, the uncle said. If sentenced to prison, he told the judge, he will be lucky to come out alive.