A Burnsville man was charged Thursday with sexual assault and kidnapping after allegedly bringing two 13-year-old Andover girls he met online to the basement of his parents' home, a case that is focusing renewed attention on online safety.

Authorities say Casey Lee Chinn, 23, met the girls through Omegle, a free online chat site, and picked them up around 7:30 Monday evening in Andover. Using clues gleaned from the girls' electronic devices, police tracked them to the Burnsville home Tuesday morning.

Chinn was charged Thursday with six felonies — two counts of third degree criminal sexual conduct, two counts of kidnapping and two counts of solicitation of a child to engage in sexual conduct.

According to the charging documents, the girls had been communicating with Chinn via text and other social media apps for about a month and the chats were "sexually explicit."

Chinn told police he believed the girls were unhappy and agreed to pick them up near where they lived. He drove them around and eventually to his home in Burnsville. He told them to enter the back door and to stay in the "basement because he lived with his parents," the documents said.

Chinn knew the girls' ages and acknowledged picking them up, the documents say.

When officers went to the Burnsville residence, he initially denied the girls were there, but eventually acknowledged that they were. When officers searched the residence, they found the two "huddled behind a couch in the basement, crying and upset."

According to the charges, Chinn engaged in sexual activity with both girls.

Chinn remains in the Anoka County jail with bail set at $300,000, with conditions.

He has no criminal record in Minnesota. He was cited for speeding in 2009, when he was 18.

Jeff Gray, Chinn's attorney, said his family is still in shock and "devastated at the allegations."

"This is so out of character," Gray said. "Casey is not the monster he is portrayed to be."

Chinn has worked at several metro-area schools and organizations as a coach, according to authorities.

On Tuesday, officials at Cristo Rey Jesuit High School in Minneapolis placed Chinn on leave from the part-time job as volleyball coach he began in September.

"We are cooperating fully with the Anoka County Sheriff's Office and are encouraging our school families to discuss any interactions that their children may have had with Mr. Chinn and to come forward with any concerns," the school said Tuesday.

Chinn also has worked as a volunteer junior varsity baseball coach at East Ridge High in Woodbury for the 2014 season.

Chinn is not affiliated with the South Washington County Schools District and "will not have an affiliation in the future," a statement from the school district said Thursday.

Local and national cyber safety experts say this latest case illustrates the risks associated with newer, lesser known mobile apps.

About 81 percent of teens use social networking sites, including Facebook, Twitter and Instagram, according to a Pew Research Center's study.

With all the hot new online sites and apps, it could be overwhelming for parents to stay on top of the new technology, said Shayla Thiel-Stern, a University of Minnesota associate professor who researches young people and social media.

"Very rarely will they be in this situation," Thiel-Stern said. "You have to have ongoing conversations about common sense and ethics … and trust your kids."

Chinn met the girls on Omegle, a free online chat site that randomly links users with strangers. Its promotional tagline is "Talk to strangers!"

Justin Patchin, professor of criminal justice at the University of Wisconsin-Eau Claire, said these mobile devices and apps, like Omegle, are extremely popular with teens and are where most of the victimization could occur.

"These apps are where they are liable to encounter strangers or people they don't know all that well," Patchin said. "But you can't watch over their online behavior 24/7. It's really important to have that dialogue and conversation."

Chinn's next court date is scheduled for Oct. 30.

Staff writers Joy Powell and Colleen Kelly contributed to this report. Karen Zamora • 612-673-4647