Negasi Zuberi locked a woman in a dungeon while posing as a police officer (Picture: US District Court for the District of Oregon)

To residents of the quiet Oregon suburb of Klamath Falls, Negasi Zuberi seemed about as close as you could get to a typical neighbour.

‘Not overly friendly’ but ‘not a jerk’, in the words of Melanie McClure, who lived next door to the 29-year-old, his wife and their two children.

He even seemed to have a Samaritan streak, risking a nasty bite from an overexcited young Doberman to help free Melanie’s much smaller dog from its jaws and give it CPR after they got in a fight in her front yard one afternoon.

Zuberi ‘was willing to step in without question and said, “you want help?”,’ Melanie told NBC News.

Zuberi is believed to have be linked to a string of grisly sexual attacks throughout the US (Picture: AP)

Little did she know that, a few months later, she would hear that her kindly neighbour was accused of being a serial violent sex attacker so far linked to five cases across the US.

For this week, Zuberi’s home played centre stage of a gruesome alleged kidnapping which also led to his arrest.

Police say he posed as an undercover officer to ‘arrest’ a sex worker more than 450 miles away in Seattle, Washington, before placing her in a makeshift cell made of cinderblocks inside his garage.

According to a criminal complaint file, waited until ‘the completion of sexual intercourse’ to declare he was a cop, showing her a badge and pointing a taser at her.

He then moved her into the back seat of his car and restrained her with handcuffs and leg irons.

Spotting a journey-planner app open on his smartphone, the woman ‘observed that Zuberi was 2 hours and 4 minutes away from his destination,’ the file states.

She ‘knew at that point that Zuberi was not a police officer and she was being kidnapped,’ it added.

The victim was trapped in a makeshift cell made out of cinderblocks in the assailant’s garage (Picture:AP)

During the journey – which would be an eight-hour drive without breaks – Zuberi ‘pulled his vehicle over and forced [the woman] to perform both oral and vaginal sex’, police say.

He then allegedly attempted to have anal sex with her but stopped after she pleaded for him to stop.

After a final stop to cover her face, he allegedly drove her to his home at 7am and locked her in the cell in his garage, telling her he ‘had to leave to do paperwork’.

Once inside the cell – which had a metal door and a single lightbulb – the woman ‘briefly slept and awoke to the realization that she would likely die if she did not attempt to escape’, the police affidavit continues.

FBI Special Agent-in-Charge Stephanie Shark, says the woman then ‘beat the door with her hands until they were bloody in order to break free‘.

Once outside, she was able to climb over a fence in Zuberi’s yard, leaving a trail of blood, before flagging down a passing motorist to call 911.

When Nevada State Patrol Officers conftonted Zuberi, he was sitting in a Walmart parking lot, speaking to his wife with one of his kids sat on his lap.

His victim eventually freed herself after escaping from the cell and fleeing his home (Picture: AP)

According to the criminal complaint, Zuberi ‘refused to exit the vehicle and cut himself with a sharp object causing him to bleed profusely.’

He is also said to have tried to destroy his phone as officers arrested him.

Following his arrest, it emerged that Zuberi may have committed further attacks while living in 12 states since 2016.

‘To date, Zuberi has been linked to at least four sexual assaults in four other states,’ Special Agent Shark said. ‘We believe there may be more victims.’

Investigations have also been opened in Washington, Oregon, California, Nevada, Utah, Colorado, New York, New Jersey, Alabama, and Florida.

The FBI has launched a national portal for victims to come forward, stating he has used other aliases including Sakima, Justin Hyche and Justin Kouassi.

According to the agency, he has ‘several different methods to gain control of his victims, including drugging their drinks, pretending to be a police officer, and soliciting the services of sex workers and then violently sexually assaulting them’.

FBI Agents said the woman’s quick thinking ‘may have saved other women from a similar nightmare’ (Picture: Google Maps)

‘Some of the encounters may have been filmed to make it appear as if the assault was consensual,’ it said in a statement. ‘The victims are threatened with retaliation if they notify the police.’

Authorities say they found a note in his home titled ‘Operation take over’ listing bullet points such as ‘leave phone at home’ and ‘make sure they don’t have a bunch of people in their life. You don’t want any type of investigation’.

Another handwritten document appeared to include a sketch of an underground structure using concrete blocks and foam insulation.

Special Agent Shark said of the woman whose discovery led to Zubari’s arrest: ‘Her quick thinking and will to survive may have saved other women from a similar nightmare.’

Negasi Zubari lived the outward life of a quiet family man – but the FBI believe he is a prolific sex attacker with victims across the US.