SURREY, B.C. -- A young man who was just days shy of his 18th birthday when he fatally beat a 15-year-old girl in a Delta, B.C., park has been sentenced as an adult to life in prison with no parole for at least seven years for second-degree murder.

The 21-year-old man pleaded guilty last year to killing Laura Szendrei in the suburban Vancouver park in September 2010. Despite the adult sentence, which would typically allow the media to publish the offender's name, his lawyer has indicated she plans to apply for a publication ban in the case.

Szendrei was walking through a forested area of the park when friends who had been waiting for her heard her screams.

They rushed to the area and found Szendrei, who was beaten so severely she died the following morning in hospital.

The murder shocked the province, not just because of the age of the young victim, but also for where it happened: a popular public park on a sunny Saturday afternoon, with nearby sports fields teeming with people.

Szendrei's parents made a tearful plea for help to catch their daughter's attacker as local residents wondered if their typically quiet bedroom suburb was safe.

In the months that followed, police set up an elaborate undercover operation, which the court heard elicited a confession from their suspect. He was arrested and charged in February 2011.

"The seriousness of this accused's criminal wrongdoing cannot be understated," provincial court Judge Robin Baird said during Friday's sentencing.

"There was a significant degree of planning and deliberation. Even if I accept that the accused left his home without the intention to kill someone, it was clear that he was resolved to commit rape and prepared to use a significant degree of violence to facilitate that intention or, if he was unsuccessful, that his victim would be incapable of bearing witness against him."

The judge's decision to impose an adult sentence prompted applause from the public gallery.

The attack occurred on Sept. 25; the killer turned 18, when he would have no longer had the protections of the Youth Criminal Justice Act, on Oct. 1.

The offender listened from the prisoner's box, wearing a white dress shirt and his blond hair cropped short, staring at the floor as the judge detailed his crime.

The provincial court room in Surrey was standing-room only, packed with dozens of family members, reporters and other onlookers. A group of reporters were relocated to the jury box to make room in the public gallery.

Szendrei's family could be heard crying as the teen's murder was detailed by the judge. Several briefly left the courtroom.

The court has previously heard evidence the attacker planned to subdue Szendrei by wrapping a plastic strap around her neck and then rape her. But the girl screamed and got away, after which he beat her over the head several times with a metal pipe.

The young man quickly fled, but he returned a short time later to gather his belongings, the court heard.

By then, Szendrei's friends were crowded around her. The attacker told the group he had heard something and even volunteered to help look for Szendrei's attacker, the court heard.

During the undercover police sting, the offender admitted he had attacked three other women several months before he killed Szendrei, the court heard.

In one instance, the attacker ran behind a woman and attempted to grab her buttocks. In another, he attempted to pull down a woman's pants while she was jogging in an attempt to grab or fondle her.

And in the third attack, he hit a woman with a stick "with an idea of disabling her" so he could either touch or have sex with her, the court was told.

The offender later told psychiatrists while in custody that he was driven by an anxiety around women due to his own lack of sexual experience.

The judge concluded the explanation was not believable and he described the man as a "sexually motivated murderer."

Last month, the man delivered an apology during his sentencing hearing, as Szendrei's parents watched from the public gallery.

"On that horrible day, I regretfully took the life of Laura Szendrei and destroyed her family," he said in late September.

"I caused terror in the Delta community, especially the friends and family of Laura Szendrei. I robbed the community of its sense of safety and its peacefulness. ... I'm not going to ask for forgiveness because I truly don't deserve it."

"No you don't," Szendrei's mother, Rachael, responded as she sobbed in gallery.

The man's sentence -- life with no parole for seven years -- is the maximum available to someone under 18 who is convicted of second-degree murder.

Had he been sentenced as a youth, he would have received a seven-year sentence, with the first four years served in custody and the remaining three served in the community.

Delta Police Chief Jim Cessford said the murder shook the foundation of the community and was especially devastating for young people.

"We conducted an extensive investigation and I'm pleased we could bring the evidence and facts and the person responsible before the courts," Cessford said in a statement.