A suspected serial predator accused of sexually assaulting four women, killing two of them, was described by co-workers as a polite, soft-spoken car salesman who mostly kept to himself.

Trent Christopher Benson made an initial court appearance Thursday and was ordered held without bond. The public defender’s office was appointed to represent him, but a lawyer has not been named.

Police in suburban Mesa said Benson has been charged with two counts of first-degree murder, two counts of violent sexual assault, three counts of kidnapping and one count of sexual assault.

Investigators watched Benson for a day before arresting him Wednesday and questioning him about four attacks that date back to 2004.

Police said Benson had a criminal record that includes arrests for soliciting prostitutes, which shocked his co-workers.

“This is unbelievable. It would be the last person that I would have expected,” said Mike Fraccola, a used car dealer in Mesa. “He seemed happy in his everyday life.”

However, Fraccola added that Benson “was always somewhat quiet and subdued. He was a little bit mysterious. No one really knows what he did with his spare time.”

Bill Fralick, a former co-worker at the dealership, said Benson told him he enjoyed strip clubs.

But “there is no way, shape or form I would have thought him capable of harming anyone,” Fralick said. “If I had kids, I would have let them be around him.”

Authorities said DNA evidence links Benson to four female victims. The first was a 21-year-old who was found strangled and partially clothed in a west Mesa alley on Nov. 4, 2004.

Nearly three years later, on Oct. 14, 2007, a 44-year-old was found strangled and raped on a west Mesa street.

A Mesa woman was abducted and raped Aug. 16, 2007, but managed to escape. A 35-year-old Phoenix woman was abducted Nov. 4, 2007, behind a business and later was found unconscious by a passer-by.

The “Barbie bandits” who went on a shopping spree and had their hair done after they were videotaped wearing sunglasses and laughing during an $11,000 bank heist have been sentenced in the US.

Ashley Miller, 19, will have to serve only two years of a 10-year sentence and must complete the rest on probation. She pleaded guilty to theft and drug charges.

Heather Johnston, also 19, was sentenced to 10 years’ probation for her role in the February 2007 heist in Acworth, northwest of Atlanta in Georgia.

The two were caught on tape as they appeared to rob a Bank of America branch in a supermarket. They admitted to plotting with a teller to take the money and later going on a shopping binge that included a stop in a fashionable hair salon.

Cobb County Superior Court Judge Mary Staley urged Miller to learn from her crimes.

“I want you to correct yourself,” Staley told Miller, a former exotic dancer. “There’s no reason you can’t become a productive citizen when you get out of jail.”

Miller’s mother and sister hugged and kissed her before deputies led her out of the courtroom.

Benny Allen - who worked at the bank as a teller - was sentenced to 10 years, to serve five.

The judge imposed an additional penalty on Allen because she said he did not testify truthfully in the trial of Michael Chastang, a co-defendant convicted of his role in plotting the heist. Chastang is to be sentenced on Tuesday.

Johnston was the first of the group to plead guilty, speeding up the prosecution of her co-defendants.

During her sentencing hearing, Johnston took the witness stand and between sobs apologised for hurting and embarrassing her family and friends.

“A lot of people look down on me,” Johnston said. “I feel terrible. I want to set a good example for my little sister. She’s a great kid. I don’t want her to end up like me.”