A former Minneapolis police officer already facing allegations that he raped a juvenile girl in Anoka County was arrested again as new charges surfaced Thursday in neighboring Hennepin County.

Bradley Schnickel sent explicit messages and photos of his genitalia to a preteen girl in Brooklyn Center last fall, according to the new charges. It's too bad we can't "hang out for a lil bit" the 32-year-old Schnickel wrote to the girl, who was 11.

Those alleged advances make up just a portion of the criminal charges now facing Schnickel, and authorities said they expect additional victims and charges as the investigation continues.

He was charged two months ago in Anoka County with three counts of criminal sexual conduct. Prosecutors there say he had sex with a 14-year-old girl and had a sexual encounter or chats via Facebook and Skype with three girls, ages 13 and 14.

Schnickel, who lives in Andover, was arrested on those charges in February and had made bail. He was arrested again Wednesday night for his alleged Internet solicitation of the Brooklyn Center preteen and one other juvenile girl. Hennepin County prosecutors charged him Thursday with four counts of Internet solicitation of children. He was being held at the Hennepin County jail awaiting a bail hearing.

The case has already led to Schnickel's dismissal from the Minneapolis Police Department, where he had worked since 2008, most recently on the city's North Side as a patrol officer. Chief Janeé Harteau called the charges "horrific" after Schnickel's first arrest. His last day on the force was Feb. 8, according to a department spokesman.

Girl's mom alerted police

The charges filed Thursday say the preteen's mother called police after seeing Schnickel's messages on her daughter's phone.

He first messaged her Oct. 19, saying in a Facebook message that he knew she was friends with another girl he was messaging. "R u in 8th like [the other girl]," he wrote, according to court papers. After talking about her age, he asked her if she was going to report him.

Schnickel repeatedly brought sex into his conversations, according to the charges, asking the girl if she was "one of the horny teens," and what she would do to him if they got together. He sent face shots of himself, along with a photo of his naked chest. In a more explicit exchange, he suggested that she see his privates and then sent her a photo of himself naked from the waist down.

Six days after his first message to the girl, her mother saw the messages and contacted police. Schnickel continued messaging the girl, asking her why she was being "so weird."

The messages were similar to those he had sent the girl's 14-year-old friend beginning in July, according to court documents. He sent the 14-year-old multiple nude pictures of himself, asked her for sex and told her he would give her money if she got some of her friends to give him sex.

Throughout the conversations Schnickel referred to himself as Brady Schmidt or Brian Schmidt.

More victims possible

During a Dec. 20 search of Schnickel's house, which he shared with his wife and two daughters, investigators took a laptop computer and a camera. A forensic examination of the computer found 4,000 references to Schnickel's aliases.

He made a first appearance in Hennepin County District Court on Thursday. An omnibus hearing was set for May 22.

The Anoka County attorney's office anticipates there will be more known victims in that county by the time Schnickel next appears in Anoka, on May 16.

Prosecutor Paul Young said that investigators continue to scrutinize thousands of printouts of teenagers' Facebook pages. Investigators have 9,000 pages of electronic evidence related to Schnickel's online conversations with "numerous juveniles," according to court documents.

"We anticipate more," Young said Thursday.

Staff writer Paul Levy contributed to this report. Matt McKinney • 612-217-1747