LUBBOCK, Texas — Monday, October 24 marked 18 years since Tammy Cooper and her three children were brutally murdered in her Lubbock home. The case has remained unsolved, according to the Lubbock Police Department.

Rey Martinez was an investigator on the case and called it one of the biggest cases Lubbock has ever had.

“That was probably one of the only cases where I have multiple children that were massacred in their own home with their mom. It just doesn’t get any worse than that. I think this is one of the biggest cases that Lubbock has ever had, and it’s still unsolved, but I still believe it can be solved,” said Martinez.

Martinez explained that sometimes people have valuable information and assume investigators already know.

“That one bit of information that somebody will turn over could break the case open,” Martinez shared. “If a subject was identified, I think there’s a great possibility that they could present a case to the District Attorney’s Office to file charges.”

LPD obtained a phone call Tammy made right before the murders. She was describing a black man she referred to as “Butch” to a friend over the phone. Martinez said he believes Tammy knew the person who killed her family, and that the black man she called “Butch” was “not from here.”

Butch showed up on the Cooper Family’s doorstep hours before they were killed, according to a friend who was on the phone with Tammy when he arrived and was invited inside.

“In talking to her friend that she was on the phone with, I don’t feel like she was in fear of the person that came in because she didn’t ask for help. She didn’t say call the police or anything, so [it was] somebody she was familiar with,” Martinez said.

The following is a statement sent to by the Lubbock Police Department on Monday afternoon in regard to the case:

“The Lubbock Police Department continues to ask for the public’s help in the 2004 murder of Tammy Cooper and her three children. While the case is unsolved at this time, our sincerest hope is that by continuing to remind the public of our department’s continued investigation, someone will feel compelled to come forward and provide additional information that will be the key piece of evidence needed to bring justice to these four victims whose lives were taken inside their home at 512 North MLK Jr. Boulevard. Anyone with information is asked to call Crime Line at (806) 741-1000.”

Related stories:

Former LPD lead investigator looks back on ‘shocking’ quadruple homicide 15 years later

Former DA looks back on Cooper family murder on 14th anniversary

Thirteen Years Since the Cooper Family Murders, Police Still Investigating

Lubbock Police Actively Investigating Brutal 2004 Murders

Investigation Continues into 2004 Murder of Lubbock Family

Still No Justice for Murdered Lubbock Mother & Children After 12 Years