He thought she was cheating on him. So he travelled across the country to confront her.
But it ended in tragedy as the 25-year-old University of Illinois student was allegedly stabbed to death by a mathematics PhD student at the same college, AP reported.
The victim, Ms Mengchen Huang, was studying in the US after leaving her home in Nanjing, China. It is believed that Yongfei Ci, 29, is also a Chinese national.
Assistant Champaign County State's Attorney Tim Sullivan said Ms Huang had told a friend that she and Ci had a troubled relationship and that she was afraid of him.
Ms Huang's roommate told police that Ci, who was studying in the US state of Rhode Island, stormed into their apartment at around 11am on Friday.
The roommate said she was bundled into a bathroom. But once Ci left, she came out and fled, raising the alarm with a passer-by.
Ms Huang's body was found by investigating officers.
An autopsy is pending to determine the woman's cause of death.
Ci was arrested a few blocks away, just hours after the slaying. The roommate was not injured.
The university police issued alerts to students and faculty, but the campus was not locked down.
Investigators used mobile phone technology to locate Ci at a motel.
Ci is a sixth-year PhD candidate studying mathematics at the University of Illinois. According to his profile on the university website, his research focuses on the topology and geometry of 3-manifolds.
Get The New Paper for more stories.