After four days of searching, the Georgia Bureau of Investigation on Monday issued a Levi's Call for a 6-year-old boy who disappeared last week from the trailer park in Glynn County.

Authorities have searched nonstop since Christopher Michael Barrios Jr. was reported missing Thursday about two hours after he was last seen near his home in the Canal Mobile Park Home. Glynn County Police Chief Matt Doering said he believes the boy was abducted, but so far no clues about what happened have emerged.

"Six-year-olds just don't typically walk off and disappear on their own," Doering said.

GBI spokesman John Bankhead said Levi's Calls — which are basically the same as Amber Alerts — are mostly used for confirmed abductions but "given the scenario, we felt it was best to go ahead and issue one."

Authorities expanded the investigation over the weekend to include checking Dumpsters, motels, dirt roads, wells and any other site where the boy could be found, the Florida Times-Union reported. Doering said officers have spoken with family members and friends, but the interviews have turned up little helpful information.

A reward of $26,000 has been offered for Christopher's safe return.

Hundreds of local, state and federal law enforcement officers, National Guard soldiers and volunteers have been looking for the boy around the Canal mobile home park, but no clues have been found. Christopher disappeared last Thursday.

Doering said officers also searched ponds nearby as well as the Altamaha Canal for the possibility he might have fallen in.

Police have expanded the investigation to people and places outside the immediate area. The Florida Times-Union reported that police Capt. Marissa Tindale said the expanded search also includes checking Dumpsters, motels, dirt roads, wells and other sites where Christopher might be found.

A toy Christopher was carrying Thursday night was found, but there has been no sign of the boy, WJXT reported.

"Please come home, and I love you," Christopher's brother said Friday during the search. "I hope he comes home. I miss him."

The 3-foot, 6-inch boy was last seen around 6:15 p.m. Thursday as he walked toward his home after playing alone at a swing set in a friend's yard in the trailer park. He was about a block from home.

He is described as Hispanic/black, about 3 feet, 6 inches tall and weighing about 60 to 70 pounds. He was last seen wearing a long-sleeve blue or green shirt, black pants and white Reebok Velcro shoes with a blue stripe.

Anybody with information is asked to call the Glynn County Police Department Criminal Investigation Division at 912-554-7802.

The Associated Press contributed to this report.