FREEHOLD, N.J. (CBSNewYork) — A New Jersey police officer finds himself on the other side of the law.

Prosecutors say the 19-year veteran cop was building a meth lab at his home, and had he not been caught there would have been a very serious risk to public safety, CBS2’s Lisa Rozner reported Monday.

READ MORE: Wild Roll To Win Against Devils

In the basement and back shed of a light grey house on West End Avenue is where the Monmouth County prosecutor says 50-year-old Long Branch officer Christopher Walls was assembling a methamphetamine lab.

CBS2 was told Walls lives there with his wife and 13-year-old daughter.

“Shock. Complete shock. Never in a million years would have suspected this,” friend Nick Luna said.

On Saturday, just after 10:30 p.m., police were called to the house for a health and wellness check and then someone in the house told them about the suspicious activity.

Soon after, officials said state and local hazmat and narcotics units found chemicals and materials consistent with a meth lab, police said.

“If you use the wrong ingredients in the slightest bit, it could result in a major explosion, taking out if not the house, potentially even like a city block,” Monmouth County Prosecutor Christopher J. Gramiccioni said.

Police also uncovered books related to making meth, explosives and poison, as well as a large open and unsecured gun safe, which had more than 12 guns and ammunition.

Gramiccioni said he does not believe Walls was working on the lab while on police duty.

READ MORE: DeRozan, LaVine Help Bulls Hang On To Beat Knicks

“When he was off duty, I would say he was always in the garage and working alone,” neighbor Joao DosSantos said. “Sometimes there were boxes going in and coming out.”

“His wife said that he started to lose weight in the past few months,” Luna added. “It’s so a shame because he really is a good guy.”

“It’s really sad. We’ve been their neighbors for four and a half years and they’ve been always very generous,” neighbor Laura Lohf said.

Sources told CBS2 Walls does not have any record of wrongdoing within the police department.

“When I was younger, he would protect me on the side of the street when people would pick on me and stuff,” Long Branch resident Vincent Corsentino said.

“This is clearly a blemish on the integrity of our profession, but the important thing is we all know it and we accept that, as does the Long Branch Police Department,” Gramiccioni said.

Walls is scheduled for his first court appearance on Thursday. He does not yet have an attorney, Rozner reported.

At this time, he is suspended from the police department without pay.

MORE NEWS: Karlsson Scores In OT To Give Sharks Win Over Islanders

Walls is also facing charges of endangering the welfare of a child. If convicted on all the charges, he faces up to 20 years in prison.