GAFFNEY — Police sketches of the suspected killer are taped to windows of downtown stores. Strangers and friends ask one another if he has been caught, or if he's struck again. And the headline in the local paper summed up the mood of this town 20 miles east of Spartanburg: "TERRORIZED."

Residents of Gaffney were frightened Friday as local, state and federal law enforcement officers hunted a man they say has killed four people in six days, in three attacks.

All the killings happened during the day. The most recent victims were shot Thursday afternoon at an appliance and furniture store near downtown, at closing time. The store owner, Stephen Tyler, 48, was killed. One of his daughters, 15-year-old Abby, was shot and seriously wounded.

"Yes, we have a serial killer," Cherokee County Sheriff Bill Blanton said at a news conference Friday.

At Pete's Restaurant in Gaffney, store owner Janice Gardner said the Tyler family frequently visited the restaurant, and she pointed to a booth where two Tyler daughters ate a week ago.

"They were very nice people, Christian people," said Gardner. She said this town of just under 13,000 people is stunned, in part because "everyone knows everyone's business."

"This is a small town," she said. "When people come in, I write down what they want to eat because I know what they are going to order. People know everyone's business. If he's from around here, someone would have recognized him, or his vehicle. The looks on people's faces — they're scared."

The killings began last Saturday about 10 miles from Gaffney, a town known to travelers for the Peachoid, a giant water tower shaped like peach on Interstate 85.

Kline Cash, 63, a peach farmer, was found shot in the living room of his home in northwest Cherokee County. Police said he appeared to have been robbed.

On Wednesday, Hazel Linder, 83, and her daughter Gena Linder Parker, 50, were found bound and shot in their home in northwest Cherokee County, about 4 miles from the first victim. The sheriff's office is trying to determine if anything was stolen.

Stephen Tyler was killed in his store Thursday, near downtown. His home address is listed near the other victims, northwest of Gaffney.

Blanton said "there is no evidence there is a hit list. There's no evidence he knows the victims. There's no evidence the victims are connected."

He said the killer is unpredictable, and that 200 investigators are working on the case.

Cherokee County, with a population 54,000, had six homicides in 2008, and three in 2007, according to The Associated Press.

Police are looking for a Ford Explorer that's gray or champagne in color, possibly from 1991-1994.

They describe the suspect as a white man, about 6-foot-2 and 230 pounds with salt-and-pepper hair.

Blanton and the Gaffney city police declined to release any details of the crime scenes. They said they were withholding some evidence to rule out false confessions.

Residents have "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."

Brad Clyde, a mechanic, said Gaffney residents are looking at each other closely.

"When you pass someone in an Explorer, you stop and look at the driver," said Clyde.

He said stores have sold out of ammunition, and that people have been driving to Spartanburg to buy handguns.

Authorities have urged sales people to stop making door-to-door calls. They also urged people not to visit friends unannounced.