SANTA CRUZ -- Surf instructor Dylan David Greiner inappropriately touched a girl three times when she was 14 and 15 years old at a Santa Cruz beach, a park and a swimming hole in the San Lorenzo Valley, according to court documents filed this week.

Prosecutors have not alleged that he had sex with minors, but the documents trace an alleged relationship that started with a surf lesson on a girl's 14th birthday and spiraled into outings and sexual advances.

At Greiner's Westside home, she found a drawing of herself in a bikini, according to the documents. In July, Greiner gave her a computer hard drive that contained more than 600 pictures -- some of which focused on her clothed private parts.

When questioned by police, Greiner wrote an apology letter to the girl that refers to inappropriate behavior, and separately he told police that he secretly recorded nude videos of another 14-year-old girl living at his house with her mother.

Greiner, 38, "demonstrated his lack of self control by graduating from a voyeur to the rank of child molester," prosecutor Rafael Vazquez wrote in a bail motion.

Greiner has been charged with lewd acts with children, possession of child porn, using a minor for sex acts, sending harmful matter, sexual exploitation of a child and possession of material depicting a child in sexual conduct -- all felonies, according to court documents.

He also is charged with unlawful invasion of privacy, a misdemeanor, and faces 10 years in prison if convicted. Greiner has not entered a plea, and he remained on suicide watch in Santa Cruz County Jail on Friday in lieu of $1 million bail. After being interviewed by police, Greiner said he no longer wanted to live, according to court documents.

At least one neighbor near Greiner's Modesto Avenue home said he knew him as a dedicated, mellow surfer -- not a child molester.

Gavin Carpenter, 19, said he sometimes surfed with Greiner off Getchell Street and hung out with him. He knew Greiner lived with a woman and her 14-year-old daughter, as well as her older teenage daughter and a college student.

It didn't seem like the child-porn den that authorities describe, he said.

"I guess everyone has dirty laundry. I guess his was just more perverted," Carpenter said of Greiner.

A BIRTHDAY PRESENT

The case started when a 17-year-old girl alleged that Greiner touched her inappropriately three times when she was 14 and 15 years old.

In 2010, the girl's parents enrolled her in Greiner's surf school as a birthday present, according to court documents. Greiner immediately took an interest in her and offered her free surf lessons.

They eventually went to the Garden of Eden, a swimming hole off Highway 9 near Felton. Jumping from a rope swing into the water, the girl's top fell off and he photographed her, prosecutors wrote. The same day, she said she had burrs in her foot. Greiner removed them and licked her toes.

He told her, "I really wanted to make out with you," according to court documents

At that point, she told him she was uncomfortable and didn't talk to him for a year.

She later ran into him at Natural Bridges State Beach. He hugged her, then he "slid his hands over her buttocks" over her swimsuit and "held on to it for a while," prosecutors wrote.

The third encounter was when the girl was 15.

Greiner met her while she was sunbathing at a grassy area near Depot Park in Santa Cruz. He sat on her back and buttocks, massaged her and rubbed against her, according to prosecutors.

Documents state that in April 2013, Greiner told her that he had a crush on her -- but it "was not a good time" because he had a girlfriend. At his house, he stroked her hair and drew pictures of her.

She noticed that he had drawings and paintings on his walls, and one of them showed her in a bikini. Greiner asked her if she wanted to do a nude photo shoot, and she declined.

DOCUMENTED EVIDENCE

In July, he gave her an external hard drive that contained photos, officials said. Prosecutors have not said why he gave it to her, but it contained a file labeled with her name. She clicked on it and found 600 photos of her -- some focused on her clothed private areas.

On Aug. 3, the teen went to police out of concern for a 14-year-old who lived at Greiner's house, according to authorities. Police searched the home, and Greiner admitted to a detective that he made secret video recordings of the girl who lived in his home while she was naked.

Greiner "admitted that he masturbated to the images," according to prosecutors. He also admitted that he took photos of young girls at the beach that focused on their clothed private areas.

Authorities seized two computers, cameras and external hard drives from Greiner's home and his Santa Cruz Surf School at 131 Center St.

Some of the images included secretly recorded videos of young teen girls changing in a dressing room at the surf school.

Santa Cruz Deputy Police Chief Steve Clark said that during interviews with police, Greiner wrote an apology letter to the original 14-year-old girl and to the Santa Cruz community.

The admissions were vague, but referenced "inappropriate behavior," Clark said.

Clark said the reason police told the media about the widened scope of the case this week was to let parents about possible victims in the past four years at Cowell Beach, Santa Cruz Surf School and in the past six months through surf lessons with the Boys & Girls Club of Santa Cruz.

Police have received dozens of calls from concerned parents since Greiner's arrest Aug. 16.

"Our goal here really is to get the information out in terms of areas," Clark said Friday. "He was doing four (surf) classes a day of 35 people. The more we find out, the larger the footprint becomes."

The surf school is still permitted to operate unless Greiner bails out of jail because he is the only person alleged to have had inappropriate contact with children, city officials said. Clark said he hopes the scope of the case against Greiner does not widen further.

"This guy needs to be off the street for as long as possible," he said.

Santa Cruz police asked possible victims in the case to email the parent's and child's names, child's age, address, family's phone numbers and date of visit to Santa Cruz Surf School the following information to investigations@cityofsantacruz.com.

Follow Sentinel reporter Stephen Baxter at Twitter.com/sbaxter_sc