A Dakota County jury on Tuesday convicted former Burnsville scoutmaster Peter Stibal II of sexually assaulting one of his scouts for at least two years, but the state is not through prosecuting him.

Stibal faces four more trials for alleged sexual assaults of three other Boy Scouts and for possession of child pornography, Dakota County Attorney James Backstrom said moments after the verdicts.

Stibal was found guilty of two counts of first-degree criminal sexual conduct involving a minor under his authority and two counts of second-degree criminal sexual conduct.

The jury was out five hours before handing up the verdict at 4 p.m. Tuesday.

Stibal showed little emotion as each of the four guilty verdicts were announced.

His father expressed disbelief after the proceeding.

"We're very disappointed," said defense attorney Fred Bruno, who had pointed out inconsistent timelines in the case.

Judge Edward Lynch, however, had instructed jurors that they didn't need to have exact dates for each incident.

Backstrom commended the young victim for his courage in coming forward and said prosecutors are "extremely pleased" with the verdict, which followed a seven-day trial.

"Justice has been served," he said.

The jury believed the Eagle Scout, now 21, who testified about four assaults that led to charges. Jurors weren't told of a fifth alleged incident in 2003, when he was 13 and at camp.

The scout said Stibal fondled and performed oral sex on him at his family's cabin near Paynesville, Minn., and at a drive-in theater in Cottage Grove. That led to the first-degree convictions. Two second-degree counts involved sexual touching at Stibal's home and at an Eagan movie theater.

The scout wasn't certain when the assaults began, thinking he could have been as young as 12. He was 15 when he told Stibal that they had to end.

Police have said the assaults on him and three other scouts happened between 2002 and 2008, with the youngest scout being only 11 when molested.

Prosecutor Amy Schaffer asked the judge to consider further testimony in support of a longer sentence; each of the first-degree convictions is punishable by 12 years in jail.

Lynch will hold that hearing later, he said.

The judge ordered Stibal jailed and his $500,000 bail canceled.

Several of his relatives were in the courtroom, as were parents of the alleged victims, some of whom wept in relief.

"It's a good day," one of them said as she left the courthouse.

Joy Powell • 952-882-9017