A Chicago man is being held on terrorism charges after he allegedly made threats aboard a Greyhound bus. The incident began late Friday night when a person aboard a bus traveling from Milwaukee to Chicago reported that man with a gun was threatening fellow passengers. Authorities began pursuing the bus in Racine county and a chase ensued through Kenosha County and into Lake County. Authorities used spike stripes along the highway near route 173 to stop the bus. They boarded the bus and arrested 33 year old Margarito Vargas-Rosas. He’s charged with making a terrorist threat, and disorderly conduct. He’s being held without bond in the Lake County Jail and will face extradition back to Racine at a hearing tomorrow. He has reportedly been deported as many as five times in the past. It remains unclear why the bus didn’t stop when officers first initiated the traffic stop, instead continuing on into Illinois.