Maddox Ritch — a 6-year-old boy with autism — went missing at a North Carolina park on Saturday, Fox News reports.

Ritch was last seen at Rankin Lake Park on Saturday at 1 p.m. said the Gastonia Police Department. Gastonia is 20 miles west of Charlotte.

While at the park, Ritch was walking with his father and two other adults along the lake. He then suddenly ran off at such a speed that he was soon out of sight of the three adults. The trio immediately searched for Ritch, though after failing to find him quickly, they immediately called the police.

Since that time, police have been immediately following up on the case, having searched 1,400 acres in the area using both a helicopter and boat — both on loan from authorities in Charlotte.

So far that search has not resulted in any leads, with Ritch still missing. Authorities have called for anyone that was present in the park at that time — which was a particularly crowded Saturday — to give any information that they may deem relevant to the local police department. Authorities are further calling on people who took photos in the park that day to provide them to law enforcement, in case a clue can be discerned.

“We know a lot of people were in the park and we have spoken to many of them but we have not spoken to everyone. No piece of information is too small. Something you may think is insignificant could be helpful to our case.”

We are searching all around the Rankin lake Park for 6-year-old Maddox Ritch. The @GPDNC SWAT team hand searched through dumpsters in the area. pic.twitter.com/ZCGuLJCBDz — FBI Charlotte (@FBICharlotte) September 24, 2018

The FBI joined the case on Sunday, with FBI Supervisor Jason Kaplan saying that the bureau has teams specifically trained to find missing children. With the FBI joining the case, an official missing child poster was released to aid with the search.

There are 24 agencies involved in the search — with the FBI and Gastonia P.D. being just two parts of what has become a huge operation, reports WCVB. The FBI has said that it is looking at every possible angle — including abduction — and is holding to the possibility that Ritch is simply lost, but alive.

Over 100 people have been involved in the search over the weekend, with rescue efforts continuing into Monday as the search radius widens.

In addition to the helicopter and boat deployed on scene, the FBI employed divers in the lake and used sonar on the accompanying watercraft in order to explore every possibility. Search dogs were also used by the authorities to try and locate the missing boy — exploring the woods beyond the park and the area immediately surrounding the lake.

So far no signs of the child have been found.

Gastonia’s Police Department has established a special tip line for Ritch’s disappearance, and is urging anyone with information to reach out at 1-704-869-1075.