The cellmate of Andrew Hernandez was strangled with a shoelace, police say, and Hernandez is a suspect in the homicide.

Hernandez was an 18-year-old senior at Guilderland High School in 2001 when he shot and killed his mother. He is now 42 and incarcerated in the Upstate Correctional Facility in the town of Malone.

On April 6, Michael J. Campbell, 51, was found unresponsive under a sheet, according to a release from the State Police.

An autopsy showed he was strangled and the death was ruled a homicide. Charges are pending as the investigation is ongoing.

On Oct. 15, 2001, Hernandez turned himself in to the police department at Guilderland Town Hall at 11 p.m. and reported he had committed a crime at the home he shared with his mother, The Enterprise reported at the time.

Officers went to the home at 6004 Gardenview Drive and found the body of Janice Hernandez, 43, in a walk-in closet off of the master bedroom, a place she used as a work station with a computer in it, police said; she had been shot once in the back of the head.

A .22-caliber rifle was lying on a couch in the living room, resting on an American flag, police said; there was a second round still in the rifle.

Hernandez’s father, José, was separated from his mother and living in Ohio; his only sibling, a sister, was away at college.

Andrew Hernandez’s high school guidance counselor at the time, Amy Arena, who had worked with Hernandez since he was in the ninth grade and also worked with his sister and mother, said he had been devastated when he was stymied in reaching his lifelong goal of joining the Marines. His 18th birthday had been on Oct. 5 around which time he had tried to enlist, she said.

“He wanted more than anything to go into the Marines,” Arena told The Enterprise the week of his mother’s murder. “He had a severe hearing loss. He found out several weeks ago, because of that, he couldn’t enlist. It was devastating for him. It had been his lifelong goal.”

A Marine recruiter, Staff Sgt. Matthew Sewell, told The Enterprise at the time that Hernandez had been disqualified on Sept. 28, 2001 for “physical limitations.” He said Hernandez had already passed other hurdles, but failed the physical exam.

Hernandez wasn’t involved in any school activities, Arena said in 2001. She referred to a form that students fill out in their junior year. “It’s totally blank,” she said of Hernandez’s form. Where students were to fill in such activities as clubs or sports or volunteer work, “He put none, none, none,” said Arena. “It’s typical of a lot of kids,” she said. “They don’t feel part of the school.”

An activity Hernandez excelled at was marksmanship.  He came in fourth, using an air gun, in the 2001 United States Field Target National Competition.

Asked about Hernandez’s friends at school, Arena said, “I don’t think he ate lunch with anyone.”

But, she said, he was closer to teachers. “He got along better with adults,” she said.

Asked about Hernandez’s relationship with his mother, Arena said, “He’s so respectful. I have kids who come in here and pummel their parents and treat them like dirt. He was very respectful of her.”

Arena said the day after the murder, “I don’t see him as a monster. I feel he’s a lonely person.” She also said, “I really want to talk to him now. I feel he’s alone….”

The high school principal at the time said Hernandez was a solid B student but had abilities that went beyond his grades.

He started attending Guilderland schools in 1993 as a fourth-grader at Westmere Elementary, John Whipple said at the time, and then went to all three years at Farnsworth Middle School, and ninth grade at the high school before his family moved to Texas; he then spent part of 10th grade at a military school in Texas and part at a public school in Ohio before moving back to Guilderland for his junior and senior years.

“He comes from a military family,” said Whipple the week of the murder, “and he planned to join the Marines.”

Asked if Hernandez had been a troublemaker at school, Whipple said, “Not at all. He had no discipline record. He was a quiet person.”

Two weeks before the murder, as part of a school assignment for a criminal justice class, Hernandez had ridden with two different Guilderland Police officers, the chief at the time, James Murley, said. “There was no indication whatsoever that this young man was any different than any of the other students from that course,” Murley said just after the murder.

The week after the murder, Hernandez pleaded not guilty to two counts of second-degree murder and his lawyer, Terence Kindlon, told The Enterprise Hernandez’s defense may assert he was “not responsible by reason of mental disease or defect.”

In July 2002, Hernandez pleaded guilty to second-degree murder, and then a year and three days after the murder, he was sentenced to 19-and-a-half years to life.

Kindlon told the judge at the sentencing that Hernandez had suffered from severe depression and had tried to kill himself four times. Hernandez remained quiet at his sentencing, waiving his right to speak.

In November 2013, a week before Guilderland school district residents voted to approve an $18 million bond issue for building upgrades, including improved safety measures, Nick Ingle, a Guilderland Police officer who was then stationed at the high school, told the school board Andrew Hernandez, was “going to attack the school.”

Ingle’s statements were the first public mention of a school attack planned by Hernandez.

Ingle described Hernandez as “a loner but bright” who was “having family problems.” His parents were separated. Hernandez “loved Dad…didn’t like Mom,” said Ingle.

Ingle also said Hernandez had “written out a plan” and was going to take guns, wrapped in an American flag, into school, where he would take a girl hostage, using her “as a human shield” before going to the rooftop where he would “shoot first responders.”

Ingle said, “He decided to test himself” by first shooting his mother.

“He said, if he could kill his own mother, he could kill people he didn’t care about,” said Ingle, concluding, “It is real. It could happen here.”

While the 2001 murder of Janice Hernandez was widely covered, police had made no public mention of any plans Andrew Hernandez had of attacking the school.