MONROE — A former Monroe police sergeant reportedly used his role as a DARE officer to groom a young woman for a sexual relationship that began when she was 14.

Former Sgt. Carlos Martinez, 58, was charged Wednesday in a Snohomish County district court with voyeurism, child molestation and sexual exploitation of a minor for incidents that allegedly began in 2003.

The alleged abuse took place over nearly 10 years, said Washington State Patrol Lt. Ron Mead, who leads the special investigations division that oversees the Missing and Exploited Children Task Force. The woman now is 24.

Martinez left the Monroe Police Department in 2009 in connection with an unrelated domestic violence investigation, Police Chief Tim Quenzer said Wednesday.

There was mixed information Wednesday on exactly when people at the Monroe Police Department first were told of the sex crime allegations. That is part of the State Patrol investigation.

Quenzer, who has been chief since 2002, said he first learned of the allegations when the State Patrol began investigating last year.

“We are extremely disappointed and disgusted with the allegations and charges that have been brought forward against Mr. Martinez,” Quenzer said. “We are very, very disgusted and disappointed with these alleged acts.”

The State Patrol began investigating Martinez in March 2012 after it was contacted by an FBI task force based in San Antonio, Texas, Mead said. Martinez had been arrested there on suspicion of possessing child pornography involving the same girl, but a grand jury decided not to indict him, citing a lack of evidence, according to articles in the San Antonio Express-News.

“As part of their investigation, they seized a number of computers and other media-type devices, and much of the content within there was used by us in substantiating the charges here in Washington,” Mead said Wednesday.

Investigators have spent time interviewing the young woman and other potential witnesses. They’ve also collected evidence from Texas, including computer hard drives and VHS tapes, Mead said.

Martinez also has been interviewed by detectives.

Much of the alleged abuse took place in Washington. Officials believe Martinez met the girl while working as a Drug Abuse Resistance Education, or DARE, officer in Monroe schools.

“In this case the victim believed this was someone who was a friend of hers, who she could trust,” Mead said. “She had every reason to believe she could trust him, and obviously he violated that trust.”

The State Patrol alleges that Martinez took sexually explicit pictures of the girl without her knowledge or consent, and continued to take pictures of her after they began having physical contact.

Martinez was not in custody Wednesday. He is believed to keep homes in east Snohomish County and Texas.

“As this investigation was ongoing, there was no indication that he was continuing to victimize anyone further,” Mead said.

Police believe Martinez may have harmed others who have not come forward.

“Many of his victims are now likely adults, and some of the people we suspected may have been victims have moved on with another chapter in their life,” Mead said.

Martinez served on the Monroe police force for 20 years.

In 2009, the department conducted an internal investigation after Martinez was accused of domestic violence involving his wife, Quenzer said Wednesday.

Court papers show the couple were going through a divorce for several years, and both of them had called police multiple times to report being assaulted by the other.

After the 2009 internal investigation was completed, Quenzer told Martinez he was considering firing the officer based on the findings. Such notifications are required under case law regarding police officers and job-related discipline.

Martinez at that point voluntarily left the department and negotiated a settlement, Quenzer said. The department agreed to pay health care costs for Martinez’ family for three months.

“We didn’t feel that his family should suffer by any means because of the actions he took,” Quenzer said.

Martinez did not receive pay under the five-page agreement, which also bans him from seeking most legal action against the city. The document, obtained by The Herald on Wednesday, says the city may have to pay some retirement benefits for him under state law.

Martinez indicated to the department that he wished to return to the military, Quenzer said. The agreement was designed in part because the department wanted to ensure Martinez no longer would be working as a police officer.

Around the time the State Patrol investigation began last year, someone called the Monroe police department asking if there was a case targeting Martinez, the chief said. The caller claimed to be asking on behalf of the U.S. Army.

Authorities now believe the caller may have been someone helping Martinez by trying to glean information about the case against him, the chief said.

In divorce proceedings, Martinez’ wife said he met the young woman when the girl was in the sixth grade, and that she had babysat for their children.

Later, Martinez and the young woman reportedly moved in together in Texas and lived together for more than two years, according to court records.

Martinez was arrested and booked into the Snohomish County Jail in 2010 for investigation of misdemeanor assault involving his wife, court papers show. His wife also sought a restraining order against him that year.

In November 2012 — after the State Patrol investigation began — Martinez went to court in Snohomish County and tried to obtain a protection order against the young woman now at the center of the abuse allegations.

In documents, he acknowledged an intimate relationship, but said it ended in October 2011. The order was denied because there were questions about where Martinez and the young woman lived, and the local court’s jurisdiction.

Martinez spent an estimated nine years serving as a DARE officer in elementary and middle schools in the Monroe School District. He already was a sergeant when Quenzer joined the department.

The department’s DARE program ended a number of years ago, along with most similar programs in the country.

Martinez also was appointed to the Monroe School Board in 2006, but was defeated at the polls the following year.

His arraignment on the sex charges is set for early August.