A 20-year-old Lawrence man has been charged with multiple sex crimes against a teenager.

Kaspar A. Engelberg was charged with three counts of aggravated indecent liberties with a child and one count of indecent liberties with a child, according to a complaint filed July 19 in Douglas County District Court. According to the complaint, the victim was 15, and the crimes began in December, when Engelberg was 19.

Engelberg’s bond was set at $50,000 in the case, according to court records. His next hearing is set for Aug. 23.

When Engelberg was charged with the sex crimes, he was already in custody on armed robbery charges.

On July 3, Engelberg conspired with a teen to rob another teen of an iPhone, while armed with a dangerous weapon, charges in that case allege. Corresponding police activity logs show the incident was reported at 1 a.m. in the 1400 block of East 24th Street.

He is charged with aggravated robbery while armed with an unspecified dangerous weapon; conspiring to commit the robbery; and contributing to a child’s misconduct by causing or encouraging a child to commit a crime, all felonies. In the same complaint Engelberg also is charged with violating a protective order, a misdemeanor.

A female co-defendant has also been charged in the robbery case, prosecutors said previously. According to the complaint, she is 15 years old.

The Douglas County Sheriff’s Office previously denied the Journal-World’s request for Engelberg’s mugshot.