He said the timeline and circumstances surrounding that deportation weren't provided.
According to investigators, at least two passengers on the bus called 911 last night around 9:45 p.m. as it made its way through Milwaukee County.
"They indicated there was a person on the bus making threatening statements and, in fact, threatening to shoot and kill," the Sheriff said.
Schmaling said passengers claimed Vargas-Rosas had a verbal altercation with at least two people on the bus. They reported he was making reference to a gun, reaching towards his waistband, and behaving strangely by walking in and out of the washroom and down the bus's aisle.
Milwaukee County Sheriff's Deputies attempted to get in front of the bus but could not, Schmaling said, so they turned the call over to Racine County.
"Several of my deputies activated lights and sirens and the bus continued Southbound into Kenosha County," Schmaling said.
He said the Kenosha County Sheriff's Department, Wisconsin State Patrol, and Illinois State Police all assisted in chasing the bus across the state line. Stop strips were used to blow out two of the tires and the vehicle eventually came to rest in Illinois.
"He made threats to law enforcement that transported him, as well as to my criminal investigators when they interviewed him," Schmaling said. "He made threats to kill them."
The suspect is currently being held at the Lake County, Illinois, jail.
He's facing charges of disorderly conduct and making terroristic threats, a felony, in Racine County.
Schmaling said the Racine County District Attorney will work through the process of having Vargas-Rosas extradited back to Wisconsin.
The suspect could face additional charges when he arrives back in Racine County.
So far, no weapon has been recovered on the bus.
"Every passenger was searched," Schmaling said. "The suspect did not have a weapon on him. However, as you know, Greyhound buses are rather large. We did seize the bus, we've applied for a search warrant, and we’ll be actively searching that bus."