PINELLAS COUNTY, Fla. (WFLA) — Several law enforcement agencies across Pinellas County are teaming up to draw attention to cold cases they want to solve.

Clear Channel Outdoor, a company that owns billboards across the county, is donating seven billboards that will highlight unsolved crimes or missing persons. The billboards will be up for two months.

The goal of the billboard campaign is to generate tips to Crime Stoppers via their tip line. A news conference is scheduled for later Thursday morning, where family members of victims of unsolved crimes will speak.

Representatives from the Pinellas County Sheriff’s Office, Clearwater Police Department, St. Petersburg Police Department and Crime Stoppers of Pinellas County held a news conference Thursday afternoon.

The law enforcement members pointed to Melanie Warren, a 15-year-old Tarpon Springs High School student killed in a drive-by shooting.

Malishia Gamble was also 15 years old. She was found in a vacant St. Petersburg lot with a gunshot wound.

“We’re hoping and we’re very hopeful that in this case and (other) cases, that these billboards will inspire someone to step forward and be the voice of these victims and become a voice for their families,” Assistant St. Petersburg Police Chief Jim Previtera said.

Deborah Martino works with Crime Stoppers. “By calling Crime Stoppers regarding these horrible crimes, you remain anonymous,” Martino said.

The Pinellas County Sheriff’s Office has unsolved homicides dating back to the 1950s. “But we continue to work ’em. We continue to look at ’em,” Sheriff Bob Gualtieri said. “It’s one of those things, you just never stop.”

Malishia’s mother talked Thursday. Coretta Gilmore said she still lives with the pain of loss after her daughter’s January 2009 death.

Justice has not been served, Gilmore said.

“I waited seven years to be able to get in front of this camera and let the world know what my daughter meant to me. Mayashia was a good person,” she said. “I’m proud to say that I’m Malayshia Gamble’s mom.”

“My daughter deserves justice,” she added.

Melanie’s mother hopes the billboards encourage people with information to come forward. Joan Blue talked about her daughter, who was killed in 1992.

“My daughter, she was a good girl, and it really just destroyed my family and my children and me,” Blue said.

The sister of another victim, Paula Withous, also spoke.

“Why would anybody any human being kill two disabled people? What purpose did that serve? And if it didn’t serve any purpose you better be careful out there because they’re still running around loose,” Sandi Clement said.

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