VALPARAISO, Ind. (STMW) — Two Northwest Indiana girls, ages 16 and 14, are accused of tying up a 17-year-old boy and sexually assaulting him.

Police said Monday the incident took place Saturday night in the girls’ residence in the 350 block of Roseland Terrace in Valparaiso, Ind.

Police said the 16-year-old girl was charged with criminal deviate conduct, sexual battery, and criminal confinement, all felonies. The 14 year-old has been charged with intimidation, battery with a deadly weapon and criminal confinement, all felonies.

Police said after luring the boy to the home, they threatened him with a knife, handcuffed him and then sexually battered him while he was handcuffed. Further details and the extent of the boy’s injuries, if any, were not specified.

The male victim eventually was able to leave the residence and reported the incident to police upon returning home, authorities said.

Police executed a search warrant on the house where the incident occurred and both suspects were interviewed by police and held at the Porter County Juvenile Detention Center. Police continue to investigate this incident.

–The Chicago Sun-Times contributed to this report, via the Sun-Times Media Wire