(CNN) -- Southern California police on Friday closed their investigation into Hollywood publicist Ronnie Chasen's shooting death late last year, concluding that an ex-convict murdered her in a random, botched robbery.
The suspect, 43-year-old Harold Martin Smith, pulled a handgun and shot himself last December as Beverly Hills detectives approached him at Hollywood's Harvey Apartments.
But despite evidence even then tying Smith to Chasen's murder last November, authorities kept the case open. Beverly Hills police Lt. Tony Lee told CNN early this year that "we hope to close it soon."
That decision came six months later. The city's police department issued a press release Friday stating that it had "completed the exhaustive investigation" by determining that Smith was "the sole perpetrator of this most heinous crime."
"All facts and evidence conclusively indicate that Mr. Smith acted alone and was in possession of the murder weapon when confronted in Hollywood for questioning" the night he committed suicide, the Beverly Hills police department said.
Chasen, 64, was driving last fall through a posh Beverly Hills neighborhood on her way home from a Hollywood movie premiere party when she was shot several times, police said.
Speculation thrived after the shooting, including a theory that a professional hit man had targeted Chasen. That was until, at least, investigators began to hone in on Smith.
"With Mr. Smith's background, we believe most likely it was a robbery gone bad," Beverly Hills Detective Sgt. Mike Publicker said in December 2010. "We believe it was a random act."
Yet authorities continued to look into the case, with Police Chief David Snowden saying then that the investigation was just "60% to 70% complete." Still, through Friday, police never indicated that anyone other than Smith was ever a suspect.
Detectives scanned 150,000 e-mails and texts belonging to Chasen, investigated thousands of tips and reviewed thousands of financial documents tied to the victim, Beverly Hills police said Friday. They also revisited Chasen's route on the night of her murder, recovered video footage and conducted numerous interviews with relatives, friends, contacts and others.
Ultimately, the most telling piece of evidence was that the gun that fired several rounds into Chasen's chest was the same weapon Smith used to kill himself when police approached to question him about her death.
"Beverly Hills police personnel assigned to this case worked in excess of 10,000 hours to thoroughly investigate each and every tip, theory and legitimate lead in order to bring this investigation to conclusion," the police statement said.