Ronni Chasen Update: Anonymous Caller Feared Retribution from Hollywood Publicist's Alleged Murderer

BEVERLY HILLS, Calif. (CBS/AP) With no motive, no witnesses and virtually no leads, the investigation into the shooting death of Hollywood publicist Ronni Chasen was nearing a dead end. Then a call from a tipster, whose fear almost kept him from coming forward, helped put an end to the murder mystery.

Chasen was shot to death Nov. 16 as she drove through Beverly Hills on her way home from a premiere party for the film "Burlesque." Four days later the TV show "America's Most Wanted" (AMW) aired its segment on the case. Three days after that, the terrified tipster picked up the phone.

According to The New York Post, the anonymous tipster said he had overheard suspect Harold Martin Smith boasting about how he killed the wealthy publicist.

In an interview, John Walsh, host of "AMW", told The Post that the tipster did not know Smith, but he was apprehensive about calling due to the ex-con's rap sheet which spans several decades.

The anonymous tipster said he had attempted to call several times and almost gave up before he finally got answer on the other end of the line.

"My family, close friends and even my doctor said I was making something out of nothing and that I should just stay out of it," he later told the show.

Despite his fear of retribution from Smith, the caller said he swallowed his fear because he knew it was the right thing to do.

"I did this for one reason," he told "AMW." "To get justice for Ronni Chasen."

When Beverly Hills police went to question Smith one week later, the 43-year-old suspect pulled a revolver from his pocket and shot himself in the head.

Preliminary ballistic reports revealed it appeared to be the same gun use to shoot Chasen multiple times in the chest.

Although the theory has been contested, police said Wednesday they believe Smith killed her as part of a robbery attempt when she stopped her Mercedes-Benz at an intersection. He apparently did not take anything and fled on a bicycle before anyone could see him in the early morning darkness.