GASTONIA, N.C. (CNN) - Maddox Ritch went missing from a North Carolina Park on Saturday.
Tuesday, his mother Carrie Ritch tearfully pleaded or anyone to come forward with information that might help find her son.
"I would appreciate it if you were at the park Saturday and saw Maddox, to please, urgently, please, call the tip line, please," Carrie said. "Continue praying for him because I just want my baby home, please. Whatever you can do."
The six-year-old was last seen with his father and another adult at the park in Gastonia, about 10 miles west of Charlotte, according to CNN affiliate WSOC.
"They were walking around the lake," Gastonia city spokeswoman Rachel Bagley told WSOC. "They got around to the back side of the lake. He started running, according to the parents, and when they started running after him, they lost sight of him, and no one has seen him ever since."
Local, state and federal authorities had expanded their search in the fourth day. They are now scouring area two miles beyond the park's boundaries, city police said.
The park's grounds include 250 acres of trails and paved walking paths, an 80-acre lake, about a dozen picnic shelters and an 18-hole disc golf course, according to city of Gastonia's website.
Police are hoping Maddox will respond to the sound of his parents voices. Officers played prerecorded messages into the sprawling park in hopes of drawing him out.
"If he's lost in the woods, he'll be able to hear those messages played, and we're hoping that he'll come to the words of his mother and his father," FBI supervisory special agent Jason Kaplan said.
Authorities are draining water from the lake to expose more of the shoreline for examination, and police are contacting businesses around the park to see if they have useful surveillance video, Gastonia police Chief Robert Helton said.
"We want to make sure that we're checking every possible spot to find this child," he said.
Helton said authorities would like to talk to an unidentified jogger who was in the park at the time, and to a professional photographer who witnesses said was taking photos of other children dressed in Dr. Seuss costumes.
The FBI also announced a $10,000 reward for information in the case.
The park is closed to the public until further notice.
Police said Maddox is 4 feet tall and weighs 45 pounds. He has blond hair and blue eyes. Maddox was last seen wearing an orange T-shirt with the words "I am the man," along with black shorts and closed-toe sandals.
Ritch said her son "is my whole world and my reason for living. He's momma's boy."