Fort Worth police have released a letter they hope leads to answers in a cold-case murder unsolved for 45 years.

Carla Walker, 17, disappeared in February 1974 after she was abducted out of her boyfriend's car at a bowling alley. Her body was discovered a few days later in a culvert near Benbrook Lake. According to police, she was beaten, raped, tortured and strangled.

The case has never been solved.

This letter was released Friday by Fort Worth police who are looking at the cold-case murder of Carla Walker, a 17-year-old who was kidnapped and found dead in 1974.

The crudely written letter, released Friday and addressed to Detective Lt. Oliver Ball, mentions Walker after some blacked-out material that may be a name. After the redacted material, the letter appears to say, "killd Carla Walker in Benbrook."

The letter ends with a P.S.: "It is hard to say but it is true."

"Sign 10100" is written before and after the postscript. A Fort Worth police spokesman said investigators aren't sure what it means but believe it is related to a police code for "dead body."

Rodney McCoy, Walker's boyfriend at the time, was in the car when Walker was kidnapped and hit over the head when she was taken.

"She was such a sweet girl," McCoy told WFAA-TV (Channel 8) last year. "I remember we were in the front seat of the car. Her back was against the passenger door. She was falling out. I went to grab her, and he started beating me over the head with a pistol."

Walker's sister, Cynthia Stone, remembers a relentless banging on her front door, which told her something was wrong.

"[McCoy] had blood just streaming down his face, screaming, 'They got her, they got her, they took her!'" Stone told KXAS-TV (NBC5) in a 2017 interview.

Fort Worth police tweeted that anyone who knows who wrote the letter — or is the author of it —should call 817-392-4307.