AURORA, Colo. -- Police have made an arrest in the homicides of two Colorado State University graduates who were engaged to be married, but the arrest is not for the killings.

Javad Marshall-Fields and Vivian Wolfe, both 22, were driving their car through an Aurora intersection June 20 when they were ambushed. Their car was shot more than a dozen times and they died instantly in a hail of gunfire. The shooting occurred just days before Marshall-Fields was suppose to testify as a key witness at a murder trial.

Police announced Friday that Parish Carter, 23, was arrested on Sept. 9 on charges of intimidating a witness. Police said he allegedly threatened Marshall-Fields the night before the shooting but investigators have not gone so far as to say he is the prime suspect in the murder case.

Police said Carter entered Gibby's Sports Bar in Aurora and confronted Marshall-Fields while he was playing pool with his friends. Carter allegedly shouted, "Javad Fields, Javad Fields. Are you supposed to be testifying?" Carter then threatened Marshall-Fields and told him to watch his back, police said.

Marshall-Fields' sister, Maisha Pollard, told investigators that her brother called her and told her that he had been threatened at Gibby's. Police then looked through the surveillance footage taken by Gibby's security cameras and matched the image on the videotape with a photo lineup of suspected gang members. Police believe the man shouting at Marshall-Fields during that encounter was Carter.

The family of the two victims are happy that investigators have made their first arrest in the case. The two mothers say they feel they are one step closer to finding the killer or killers.

Christine Wolfe and Rhonda Fields have been very active in keeping the children's case in the media spotlight and have raised $25,000 for a reward leading to an arrest.

Anyone with information regarding the case is asked to call Aurora Police Department at (303) 739-6013 or Crime Stoppers at (720) 913-STOP (7867).