Before he was sentenced to seven years in prison Friday, Johnny D. Guillen Pimentel stood before a judge to give his first comments on a series of crimes so strange it transfixed the region: He slashed the buttocks of young women at shopping malls.

“I’m very remorseful for all the things that are occurring,” the Peruvian native said through an interpreter at the sentencing hearing in Fairfax County. “I ask you to pardon me.”

The 42-year-old former Fairfax resident then stopped abruptly, leaving unsaid the thing about the 2011 attacks that has long baffled prosecutors, the public and even a friend of his in the courtroom: Why did he do it?

The mystery endures.

“We still don’t know what awful and bizarre motivation he had,” Assistant Commonwealth’s Attorney J. David Gardy said in court. “But we know the action was a terrible one.”

Johnny D. Guillen Pimentel (Courtesy of Fairfax County Police)

Fairfax County Circuit Court Judge David S. Schell gave Guillen Pimentel the maximum sentence possible under a plea deal the defendant reached with prosecutors in June, but he said the slashings were “unique” and could have warranted more prison time.

The attacks began on Valentine’s Day 2011 at the Fair Oaks Mall. A 20-year-old woman was leaving the mall laden with shopping bags when a man rushed up behind her and cut her backside with a hobby knife.

“I thought he was grabbing me at first, and then I felt my skin. I was like, ‘You just ripped my leggings,’ ” she said in an interview about six months after the attack. “He said, ‘No, no, no — it was the bag’ and ran away really fast.”

The attacks that followed at Tysons Corner Center and the Greenbriar Shopping Center were similar. In each case, a man rushed up behind a woman in her teens or early 20s, slashed her and then melted away — often before the woman knew what happened.

As the attacks mounted over a number of months, the cases drew more news media attention and prompted the police to form a task force to find the culprit. None of the slashings caused serious injuries, but they left shoppers on edge.

Police eventually released still images of the suspect from surveillance footage and issued an arrest warrant for Guillen Pimentel in September 2011 after he had been identified. About that time, Guillen Pimentel fled to Peru, where he was arrested in Lima in January 2012. He was eventually extradited to Fairfax County.

Guillen Pimentel pleaded guilty to two counts of malicious wounding and two counts of unlawful wounding in four of the nine attacks. Prosecutors dropped the charges in the other cases as part of the plea deal.

On Friday, a half-dozen of Guillen Pimentel’s friends and family members sat in the courtroom in support of him. It did not appear that any of the victims attended the hearing, and prosecutors did not read impact statements from them.

The prosecutor said it is likely that Guillen Pimentel will be deported to Peru after he finishes serving his sentence.

Afterward, a friend of Guillen Pimentel’s struggled to reconcile the crimes with the man he knew.

“He’s very nice and normal like any other person,” Euclides Paredes said. “He was working for some companies. . . . [Then] this happened.”