Thomas Innerebner, depicted in a sketch by a court artist, was sentenced Saturday to seven years in prison. (CBC)

An Edmonton taekwondo instructor has been sentenced to seven years in prison for a series of sexual assaults on children.

Thomas Innerebner, 52, was found guilty in December of six counts of touching children under 14 for a sexual purpose and seven counts of sexual assault.

Court of Queen's Bench Justice Donna Read issued the sentence in an Edmonton courtroom Saturday.

Innerebner sat beside his lawyer with his fists clenched in his lap, shaking his head as Read described the testimony of the victims.

Outside the courthouse, one victim's father said he was unhappy with the sentence.

"The judge pointed out dozens of cases and everybody talked about sending out a deterrent, and as the judge spoke about all these cases, all the same sentencing — obviously the justice system isn't getting it," he said.

"These aren't a deterrent to these people and these people can't be fixed."

Described as monster

He said the trial has had a huge impact on his family.

"It's been just about three years of putting up with knowing this monster's out there able to do it to other people's children. … It certainly has an effect," he said.

"I don't know what type of long-term effect it'll have on my daughter, but hopefully we can minimize that."

Innerebner was acquitted on four charges relating to three of nine female complainants.

During the trial, the jury heard the assaults took place between 1998 and 2007. The victims were between seven and 15 years old, and most of the assaults took place during or after Innerebner's taekwondo classes.

Innerebner maintained his innocence throughout the trial, denying he ever assaulted or touched any of his students inappropriately.

"I do not have a violent or dangerous bone in my body and I have a very big heart," he said in court Saturday.

His lawyer, Brian Beresh, said the outcome is disappointing.

"To see a man who has devoted his life to training young people, spending thousands of hours with all kinds of people, thousands of kids, and these complaints are made in a public setting where they are not witnessed by one other person, it's just hard to believe," he said.

"I said at the end of the trial that the decision of the jury is perverse, [and] I maintain that view. It's still a wonder as to how that occurred, but my client will be appealing both conviction and sentence and I expect that will be filed fairly quickly."