Margarito Vargas-Rosas, 33, was arrested after allegedly threatening to shoot and kill fellow bus passengers aboard a Greyhound bus Friday night. (Racine County Sheriff's Office)
A man aboard a Greyhound bus who allegedly threatened to shoot and kill fellow passengers on Friday, leading police on a chase that began in Wisconsin and ended in Illinois, is an illegal immigrant, and is now facing terror charges.
Police responded to a call around 9:40 p.m. Friday from a bus passenger who claimed there was a person threatening to kill people, Fox 6 reported, citing the Racine County Sheriff’s Department.
Margarito Vargas-Rosas, 33, of Chicago, was reportedly pacing the aisle toward the back of the bus, and appeared to draw what passengers thought was a weapon from his waistband.
Deputies with the Milwaukee and Kenosha County Sheriff’s Offices both attempted to pull the bus over, but the driver didn’t stop the vehicle.
Racine County Sheriff Christopher Schmaling said the bus driver “thought it was a training exercise by law enforcement, or thought he was going to stop someone.”
Passenger Patrick Todd told The Chicago Tribune the bus occupants were confused by the driver's actions and kept yelling at him to pull over.
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Authorities ultimately used spike strips to flatten the vehicle’s tires, which forced it to a stop on Interstate 94 near the Illinois community of Wadsworth.
While the bus eventually stopped, the driver, according to Dodd, “didn’t stop after the first spike strip, he went on to Illinois” before hitting the second spike strip.
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Another passenger, Terrance Williams of New Jersey, said he thought police were escorting the bus, not realizing what was happening in the back. He was also confused about why the bus driver took so long to pull over.
"The law is, you see emergency lights, you pull over," Williams said. "(The police) were in front of us, they were in back of us."
“I think he ultimately recognized that this was a serious event when we spiked his tires,” Schmaling said of the driver.
Vargas-Rosas was ordered off the bus at gunpoint, according to Fox 6, and was taken into custody without incident. Schmaling said the man made threats to law enforcement as he was being transported to jail.
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Officials didn’t locate a weapon on Vargas-Rosas, but said the bus will be thoroughly searched.
None of the nearly 40 people aboard the bus were injured.
Vargas-Rosas is in the U.S. illegally, and was previously deported to Mexico in 2012, The Daily Herald reported.
Vargas-Rosas reportedly faces charges of felony terroristic threats and disorderly conduct.
The Associated Press contributed to this report.
Nicole Darrah covers breaking and trending news for FoxNews.com. Follow her on Twitter @nicoledarrah.