The frantic search for Faye Marie Swetlik, a 6-year-old girl who mysteriously vanished in front of her South Carolina home Monday, has entered its fourth day as hundreds of police and FBI investigators continue piecing together evidence.

Investigators are now looking for the drivers of two unfamiliar vehicles seen in the Churchill Heights neighborhood of Cayce, S.C., around the time Faye was last seen.

The Cayce Department of Public Safety late Wednesday released new video of the cars, which appear to be a Chevy Trailblazer SUV and a sedan. Police said they hope to identify and interview the occupants.

The vehicles police are searching for appear to be an older model Chevy Trailblazer SUV and a sedan.

The vehicles police are searching for appear to be an older model Chevy Trailblazer SUV and a sedan. (Cayce Department of Public Safety)

“We’re still exploring every possibility to bring Faye home,” Cayce Public Safety Officer Sgt. Evan Antley said Wednesday.

No evidence has pointed to a kidnapping, but investigators said they have not ruled out abduction or other possibilities, like she walked away from her home or was harmed by someone she knew.

Investigators are circulating pictures of Faye in an effort to aid their search. The left photo is about the length of Faye's hair now, police said.

Investigators are circulating pictures of Faye in an effort to aid their search. The left photo is about the length of Faye’s hair now, police said. (Cayce Department of Public Safety)

The 3-foot-10 inch, 65-pound first-grader vanished around 3:45 p.m. Monday shortly after getting off her school bus. She was last seen playing in front of her home. Family searched for Faye for about an hour before calling 911, authorities have said.

“Her mother, her mother’s boyfriend and her father have all been cooperative with us,” Cayce Public Safety Director Byron Snellgrove said.

Police released video of the 6-year-old exiting the bus in her last known outfit: polka dot rain boots, a pink flowered skirt, and a black T-shirt with a neon design and the word “PEACE” written on front. She recently had her hair cut to shoulder-length.

Investigators have said that in the course of the first 72 hours, investigators sent more than 250 officers from multiple agencies out to canvass the neighborhood, going door-to-door to every house and even searching some homes. Hundreds of hours of video were scrutinized and witnesses interviewed.

Helicopters have been flying over the neighborhood since Monday, and tracking dogs have combed the streets in search of clues. The search also included nearby wooded areas.

Police said an Amber Alert has not yet been issued because the situation does not meet federally mandated guidelines, which call for evidence that an abduction has occurred along with enough information to aid in the child’s recovery.

Flyers with Faye’s picture were posted all over Cayce, a city of 14,000 neighboring the state capital of Columbia.

“Faye is a bubbly energetic first-grader at Springdale Elementary School,” Snellgrove said. “When she walks into a room, she brightens it up.”

The department also provided a tip line, (803) 205-4444, for anyone with information to call.

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