A Dallas police officer was arrested today for allegedly raping a woman he'd pulled over.

According to a DPD news release, officer La'cori Johnson stopped a vehicle on the 9300 block of Larga Drive on September 9, 2013. Johnson told the woman driving the car that she had an outstanding warrant and that he'd have to take her to jail -- unless she had sex with him.

"He then took her to a nearby location where he forced her to have sex," the release says. "Johnson then released her at another location. The victim subsequently made an outcry which was reported to the Dallas police."

The victim alerted police in October, and Johnson was placed on administrative leave that day, police say. A "public integrity investigation" was launched "first" -- the department hasn't said when -- and an internal affairs investigation was launched last week, almost three months after the incident was reported.

Johnson, a five-year veteran of the department, was questioned by internal affairs investigators today and promptly resigned, police say. He's charged with sexual assault, a second-degree felony.

This story was updated to correct errors made in the police's initial press release and to include additional information.

Send your story tips to the author, Eric Nicholson.