CONCORD -- A Concord police officer has resigned from his job as he faces charges of burglary and elder abuse for taking prescription drugs from residents at a seniors complex, prosecutors said Friday.

Matthew Switzer, a 12-year veteran of the Concord Police Department who serves as a K-9 officer, is being held in lieu of $480,000 bail at the County Jail in Martinez. Switzer, who worked with a German shepherd named Figo, resigned from the department Friday afternoon.¿

During his first court appearance Friday afternoon, Switzer listened as Judge Bruce Mills read the charges: two counts of first-degree burglary, one count of second-degree burglary, one count of fraudulently obtaining prescription drugs and one count of elder abuse.

Switzer's attorney, Harry Stern, said Switzer is a "good officer" and "well respected."

He said Switzer had sustained a neck injury while on the job and was prescribed Norco for treatment.

Norco is used to relieve moderate to severe pain, but it does contain hydrocodone, a highly addictive opioid, according to a website for manufacturer Actavis, Inc.

Stern said Switzer also suffers from post-traumatic stress disorder, but he did not say when Switzer was injured or what the stress stemmed from. Stern said the combination of ailments led to Switzer's addiction.

"This is about the tragedy of prescription drugs and addiction," Stern said. "(Prescription drugs) are the most abused drugs in the country, and the numbers are only going up."

Stern added that Switzer had been "aggressively attacking" his addiction but that the battle to beat it was a day-to-day process.

"(Norco) is basically pharmaceutical heroin, and he succumbed to it" Stern added. "We are optimistic he can beat it. He's struggling right now, but we believe things will get better for him. It's just going to take some work.".

The charges came after an extensive investigation by the District Attorney's Office initiated at the request of Concord police Chief Guy Swanger in February.

According to Swanger, someone alerted police that Switzer, 38, was allegedly stealing prescription drugs. Swanger did not say where Switzer was reportedly getting the drugs or from whom.

Switzer is charged with using his status as an officer to enter the apartments of several senior citizens to steal prescription drugs,¿ Peterson added.

According to criminal complaint, the thefts took place between October 2013 and February 2014 at a senior housing complex called The Heritage in downtown Concord, as well as an occupational medicine facility operated by John Muir Health.

A spokesman for The Heritage said Friday he was aware of the investigation but refused to comment.

Switzer is scheduled to appear at 1:30 p.m. Tuesday in Contra Costa Superior Court.

Staff writer Gary Peterson contributed to this report. Follow Katie Nelson at Twitter.com/katienelson210.