New details have emerged about an incident involving NFL quarterback Johnny Manziel and his ex-girlfriend, who is a TCU student.

According to WFAA/Channel 8, Colleen Crowley, a general studies major, told police on Jan. 30 that Manziel told her “shut up or I’ll kill us both” while driving home from Dallas on Jan. 29. Manziel also reportedly struck her multiple times and drug her by the hair during the incident.

Manziel later denied the allegations to TMZ.

According to WFAA, Crowley is preparing to file a protection order with a Tarrant County judge. Manziel and Crowley dated for more than two years but broke up in December.

Initial reports described how, following the incident, police conducted a search for Manziel in Fort Worth. He was not arrested that night.

The Fort Worth Police Department said it would work with Dallas police in the investigation. The Dallas Police Department issued a statement today saying it had closed the case.

“The Dallas Police Department has conducted the appropriate investigative follow-up to the report forwarded to us by the Ft. Worth Police Department regarding an alleged incident involving Johnny Manziel,” the statement read. “Investigative efforts to date have not resulted in the filing of a criminal complaint and the incident is determined to be closed.  No further statement is expected at this time.”

Fort Worth police are still investigating the incident.

Manziel was a star quarterback at Texas A&M University and the first freshman to ever win the Heisman Trophy. He was selected by the Cleveland Browns in the first round of the 2014 NFL draft, but he has struggled with off-the-field issues ever since.

Manziel is still on the Browns’ active roster, but reports say Cleveland will cut Manziel before next season.

Click here to read the entire WFAA/Channel 8 report about the incident involving Manziel and his ex-girlfriend.