GAFFNEY, S.C. — A terrified rural South Carolina community hunkered down over the Fourth of July after the sheriff said a serial killer was on the loose, and longtime residents were reminded of a murderer who terrorized the town in the 1960s.

Memories of the "Gaffney Strangler" were reignited this week after authorities said a new serial killer gunned down four people during three separate incidents over several days. Authorities have released a sketch of the accused killer and a description of the sport utility vehicle he may be driving, but they have been silent about exactly what has linked the slayings.

The town of Gaffney, about 50 miles south of Charlotte, N.C., is located in a county that had just six homicides in all of 2008, and half that the year before. The last time the town was this threatened like this was when the "Gaffney Strangler" killed four women over 10 days in 1968 and vowed to kill more. The town banded together, despite racial prejudice, to find the man who was killing both white and black women.

The strangler, Lee Roy Martin, called the editor of a local newspaper on Feb. 8, 1968, and told him where to find the bodies of two women he'd dumped in the woods. He threatened to kill even more women until he was "shot down like the dog I am."

People started to comb the community for clues, which led to Martin's arrest. He was convicted of four murders and sentenced to four life terms. In 1972, he was stabbed to death in his cell.

The latest killings have residents on edge, with "their guard up and their gun handy," said state Sen. Harvey Peeler, R-Gaffney.

"There is no greater fear than the fear of the unknown and nobody knows. You can cut the tension with a knife," Peeler said. "People are locking their doors, even in broad daylight."

Tanya Phillips had been looking forward to a backyard barbecue at her brother's house but instead planned to stay home with her doors locked.

"I'm not taking any chances," said Phillips, 32, a mother of two who works in a day-care center. "I'll go out during the day, but not at night. I just don't feel safe."

Every available police officer will work the weekend, Cherokee County Sheriff Bill Blanton said, acknowledging there is "real fear in the county." He urged people to take precautions such as going out in groups and calling 911 if their cars break down and they are stuck on the side of the road.

The latest victims were found in their family's small furniture and appliance shop near downtown Gaffney around closing time Thursday. Stephen Tyler, 45, was killed, and his 15-year-old daughter was shot and seriously injured. Family members and a store employee found them in the Tyler Home Center.