By Jennifer Mayerle

MINNEAPOLIS (WCCO) — A Twin Cities teenager who pleaded guilty to trying to join ISIS is going back to prison.

A judge had let 18-year-old Abdullahi Yusuf live at a halfway house in St. Paul ahead of his sentencing. But on Monday the government said he broke the rules, so he’s going back into federal custody.

Investigators stopped Yusuf at the airport last spring before he could fly to Turkey. In February, he pleaded guilty to trying to help ISIS.

It’s unclear what Yusuf is accused of doing at the halfway house that’s sending him back to prison.

Jennifer Mayerle