DETECTIVES investigating the baffling abduction of mum-of-two Sherri Papini flew almost 2,500 miles to the city of Detroit, Michigan in the days after she went missing.

Police expense reports show that two detectives travelled to Detroit between November 9 and November 11 last year — at the height of Ms Papini’s disappearance.

9 Sherri Papini was dumped on the side of the road in chains after 22 days in captivity

9 Sherri was kidnapped while she was out jogging near her home in Redding, California Credit: WENN

9 Sherri with husband Keith and their children Tyler and Violet Credit: WENN

9 Cops from the police force investigating Sherri's kidnap flew to Detroit, new records reveal Credit: WENN

The documents filed by the Shasta County Sheriff’s Office in California were obtained by The Sacramento Bee under the state's Public Records Act after the paper asked for all reports relating to the case, beating a media blackout imposed by Sheriff Tom Bosenko.

Ms Papini was kidnapped while jogging near her home in the small town of Redding in northern California on November 2.

She was found beaten, branded and half starved on the side of a motorway in Yolo County — more than 120 miles from where she was last seen — in the early hours of Thanksgiving Day.

The petite blonde told police she had endured repeated abuse at the hands of two Hispanic women during her 22 days in captivity.

But the 34-year-old has been unable or unwilling to provide a detailed description of her attackers, fuelling speculation of a hoax.

Ms Papini claimed she never got a good look at the women because they kept their faces covered — or covered hers — for most of the time.

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Some have suggested that she is withholding crucial information relating to her abductors’ identity out of fear that they will come back for her or her young children.

One of the strongest theories is that Ms Papini — who looks young for her age — was taken by sex traffickers and supporters point to her branding as evidence of this.

Professionals who have worked with former sex slaves say branding is a common practice in the evil industry.

The FBI lists branding as a “physical indicator” of sex trafficking, used by perpetrators to declare “ownership” of the victim.

9 Sherrif Bosenko, right, has refused to give further details on the case until the investigation is complete Credit: WENN

9 Sherri says she was abused by two Hispanic women, but has not given further details Credit: WENN

Sheriff Bosenko refused to discuss what lead detectives to Detroit or what clues, if any, they had found there.

But a statement issued by his office two weeks after Ms Papini vanished said detectives were searching for information that would indicate whether her disappearance was “voluntary or involuntary”.

Detectives combed through bank records, social media accounts, mobile phone data and emails.

They were also interviewing family, friends and ex boyfriends.

“This type of follow-up has taken detectives out of state in the hopes Sherri could be found,” the Sheriff’s statement said.

But it can now be revealed that the Michigan trip may hold significance for another reason.

On November 18 — just one week after the search for Sherri Papini led two Shasta County detectives to Detroit — police in that city busted a major sex trafficking ring.

A raid on a home owned by Richard Knider in the suburb of South Electric resulted in a horrifying discovery: Knider had kept four women, two of them underage, imprisoned inside the property.

He allegedly plied them with drugs, forcibly injecting them with heroin until they were hooked and then selling them to clients for sex.

Two teenage girls Knider allegedly trafficked managed to escape from the house just hours before it was raided, Detroit News reported.

They remain in hiding despite national appeals for them to come forward so they can receive assistance.

Sheriff Bosenko has declined to say what investigators think of the sex trafficking theory and the timing of the Detroit trip may be nothing more than coincidence.

Neither authorities or family members have provided any insight into a motive behind Ms Papini’s kidnap, or why her captors risked arrest by releasing her instead of killing her when they had the chance.

9 Mum-of-two Sherri was branded, leading to speculation she may have been kidnapped for the sex slave trade Credit: WENN

9 Husband Keith was distraught during Sherri's disappearance in November Credit: WENN

9 The investigation into Sherri's disappearance is expected to last a long time Credit: WENN

The case became an international media sensation, spawning dozens of conspiracy theories.

Scepticism intensified after Cameron Gamble, a Redding-based “kidnap and ransom expert” offered Ms Papini’s captors a six-figure cash sum in exchange for her safe return after he was gifted the money by an anonymous donor.

The tactic, known as a “reverse ransom”, failed in the sense that the kidnappers never took the money — but Mr Gamble’s ransom video went viral and generated a blaze of publicity.

Ms Papini was found less than 24 hours later.

Meanwhile Sheriff Bosenko’s news blackout continues.

On November 30, he told a press conference that no new information would be released while the case was being investigated.

Asked last week whether he expected a resolution anytime soon, Sheriff Bosenko said it was impossible to say.

“You never know on these cases,” he told The Sacramento Bee. “Tomorrow, there could be a major break in the case. You just don’t know.”

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