The ex-convict convinced the woman he was a detective, the charges say. He then kidnapped her and, after raping her repeatedly, scrubbed her entire body in bleach before freeing her and giving her bus fare, they say.

Gideon Charles Arrington II, 35, who previously had been convicted of armed robbery, was charged Thursday in Anoka County with felony sexual assault and kidnapping in the Nov. 23 abduction of a woman near Fridley City Hall.

The assault occurred just before two other late-November attacks on women near the University of Minnesota campus in Minneapolis, one of which also involved a suspect posing as a law enforcement officer. Authorities now say the rapes involving police impostors appear not to be related.

Using bleach to conceal a sexual assault is “highly unusual,” said Anoka County Sheriff’s Cmdr. Paul Sommer. “He had this planned pretty well.”

The university declined to comment after Arrington’s arrest. But Minneapolis police, who were privy to information gathered by Anoka County authorities, said in a statement from police spokeswoman Cyndi Barrington that the department “does not have any evidence that leads us to believe that the [sexual assault] that occurred in Minneapolis on Nov. 24, 2013, is related to the [sexual assault] that occurred in Fridley.”

Arrington, of Brooklyn Park, remains in the Anoka County jail in lieu of $1 million bail.

The 32-year-old victim told police she was getting into her vehicle near where she was assigned as a personal care attendant. She said that Arrington told her he was a detective and later stuck something in her back and said he would shoot her if she didn’t get into his vehicle.

The woman told authorities she was handcuffed, blindfolded and driven to an unknown location, where Arrington raped her at least twice over a few hours, threatening to kill her.

After each assault, the woman said Arrington “scrubbed her entire body with a bleach-type solution.” He also took her clothing and washed it.

According to court records, Arrington and the woman traveled in his Ford Explorer for about 10 minutes and stopped. He removed her blindfold, put $2 in her coat pocket and told her to walk to a bus stop.

“It was dark and very cold, and … she was very fearful and had no idea where she was,” the complaint continued. The woman flagged down a cab, and the driver called police.

During a hospital exam, semen was taken from the woman’s body. DNA analysis found a match in a convicted-felon national database. That led authorities to arrest Arrington.

In Minneapolis, a somewhat similar attack occurred the next day near the University of Minnesota. That suspect also was reported to be impersonating a law enforcement officer. Police say the student had been walking alone about 2:15 a.m. near 8th Street and 15th Avenue SE. She told police that the man warned her against walking alone and offered her a ride, then drove to a remote location and sexually assaulted her.

In 2009, Arrington was convicted of committing an aggravated robbery in Brooklyn Park and was imprisoned until August 2011, according to the Minnesota Department of Corrections. His supervised release expired on Dec. 19, 2012, a corrections spokeswoman said.

Arrington is scheduled to appear in court Jan. 10.