CHICAGO (CBS) — A 17-year-old boy was charged Monday with sexually assaulting a girl at a party she hosted over the weekend in Elmhurst.

The boy was ordered detained by DuPage County Judge Joshua Deiden on Monday, on two counts of criminal sexual assault, according to the DuPage County State’s Attorney’s office. The boy’s name was not released.

Prosecutors said on Saturday, the boy showed up at a party the girl was hosting, and at one point, he was asked to leave and did so. But he later returned – forcing his way in by breaking down the back door, prosecutors alleged.

Once inside, the boy allegedly grabbed the girl, told her, “I’m going to kill you,” and sexually assaulted her, prosecutors said.

“The allegations against this defendant, who, after being asked to leave, allegedly broke down a door to get back into the party and then threatened to kill a female friend before sexually assaulting her, are extremely disturbing and will be met with the full force and effect of the law,” DuPage County State’s Attorney Bob Berlin said in a news release.

The boy is due back in court on Tuesday in front of Judge Robert Anderson.