ST. CHARLES (CBS) — A martial arts instructor already being held for sexually preying on a minor was indicted Tuesday for having sexual contact with two teenagers.

Dean Fuerstenberg, 43, of Eden Prairie, Minn., was indicted by a Kane County grand jury on four counts of criminal sexual assault and six counts of aggravated criminal sexual abuse, a release from the Kane County State’s Attorney’s office said.

The alleged sex acts took place at a South Elgin karate school.

According to the indictment, between June 1, 2003, and Nov. 30, 2005, Fuersten­berg took advantage of his position of authority as a karate instructor and engaged in sexual acts with two girls who were over age 13 but younger than 18.

According to the indictment, he touched the girls’ breasts, buttocks and vaginal areas; forced them to touch him; and had sex and oral sex with them.

After the indictment was read, a Kane County judge ordered Fuerstenberg held on a $750,000 bond, the release said.

In August 2011, Fuerstenberg was indicted in DuPage County on two counts of predatory criminal sexual assault of a child and four counts of criminal sexual assault, the release said.

DuPage County prosecutors allege that between May 2001 and May 2006 at a Roselle martial arts school, Fuerstenberg engaged in sexual acts with a victim younger than 17.

Fuerstenberg has been in custody at the DuPage County jail on a $700,000 bond.

The Kane County case remains under investigation and anyone with additional information about Fuerstenberg should call Det. Sgt. Mike Doty of the South Elgin police at (847) 741-2151.

(Source: Sun-Times Media Wire © Chicago Sun-Times 2012. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)

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