Investigators believe the body of 4-year-old Raul Gonzalez Johnson has been found in a pond off Peabridge Road in Laurinburg, FBI officials said.

Officials said the Scotland County Medical Examiner's Office must still confirm the identity and cause of death, but Gonzalez Johnson's family has been notified.

Crews continued their ground search Saturday for Raul.

Officials said about 150 searchers covered areas near his home, and that crews drained a nearby pond.

The FBI announced Friday that it assisted in the search, and fire crews from Charlotte and Mooresville also joined in the efforts.

A North Carolina Amber Alert was issued earlier this week.

Investigators said Raul's grandfather was watching him and when he lost track of the little boy, and then called 911.

Raul was last seen on Village Drive walking toward Crestline Road in Laurinburg.

"Most of it is going to be rural, so we'll go walking through a lot of fields, a lot of forest, thick brush, things of that nature,” Charlotte Fire Deputy Chief Rich Granger said.

The State Bureau of Investigation was also involved with the search, which included the use of dogs, drones and dive teams.

"The folks that we sent all are fathers and have children themselves, so naturally, it adds to the urgency of the situation and the hope to have a successful outcome and do the best they can," Capt. Rob Colvert with the Mooresville Fire Department said.

More than 300 volunteers and numerous agencies were involved in the search.

Charlotte Fire sent mobile communications units for everyone to keep in contact.