OCEANSIDE, Calif. -- An Oceanside police sergeant pleaded not guilty Thursday to theft and conspiracy charges involving tens of thousands of dollars worth of valuables he accepted from a girlfriend while allegedly knowing the items were bought with embezzled funds.

Walter Willis McWilson, 37, surrendered to the custody of the county Sheriff's Department Thursday afternoon, shortly before being arraigned at the Vista Courthouse on seven counts of receiving stolen property, six counts of grand theft and one count of conspiracy.

The Murrieta resident -- a 10-year member of the Oceanside Police Department -- faces up to five years in prison if convicted of all the charges. He was ordered held on $10,000 bail.

The charges stem from about $54,000 worth of gifts McWilson allegedly accepted from then-girlfriend Aimee Rich over a roughly yearlong period in 2006-2007, OPD Capt. Tom Aguigui said.

Rich used a credit card owned by the construction company where she worked to buy flat-screen television sets, household goods, gift cards, exercise equipment, musical instruments, restaurant meals and other valuables for McWilson, who allegedly took them knowing that they had been obtained through theft, Aguigui said.

The sergeant allegedly used some of the items to outfit a home recording studio he was building at the time.

Police began investigating the alleged crimes in May 2008, when Rich's employers, the owners of Royal Pacific Construction in Oceanside, reported the embezzlement.

Detectives first identified McWilson, who stopped dating Rich several years ago, as a witness in the case. As the investigation continued, the sergeant emerged as a suspect, Aguigui said.

The police department put McWilson on administrative leave in August.

Rich pleaded guilty to a felony embezzlement count and is awaiting sentencing, the captain said.

A preliminary hearing to determine if there is enough evidence to order McWilson to stand trial is scheduled for Dec. 9.