Jacksonville Sheriff Mike Williams is urging residents in the area where two children went missing Sunday to search their properties. "Under trailers, abandoned cars," he said during a news conference Monday.

Williams said the parents of 6-year-old Braxton Williams and 5-year-old Bri'ya Williams were home when the children disappeared at about 11:30 a.m.

"The family has been and remains cooperative," Williams said. "Right now everything is an option."

JSO released an incident report Monday, nearly 24 hours after Braxton and Bri'ya were last seen playing in a front yard in the Paradise Village mobile home park.

The children's father, Bryan Williams, told officers he was outside setting up for a bar-b-cue and the children were outside with him, according to the report. He told officers he noticed his two children were no longer outside with him at about noon and he tried to find them.

Bryan Williams called 911 to report them missing, the report states.

JSO Public Information Officer Christian Hancock said Sunday family members searched for an extended period of time before reporting them missing to JSO at around 1:30 p.m.

Braxton & Bri’ya Williams
Braxton & Bri’ya Williams
Jacksonville Sheriff's Office

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K9s, a dive team, aerial units and drones have been deployed to aid in the search. Officers are also knocking on doors and handing out flyers in surrounding neighborhoods in addition to passing out flyers and stopping cars coming and going from the mobile home park. The Jacksonville Fire and Rescue Department, Urban Search and Rescue team, as well as dogs from other agencies and some private entities, are also searching for the missing siblings. 

"We're not going to spare any expense, the search will continue throughout the night as it's going right now until we find these children," JSO Public Information Officer Christian Hancock said Sunday. "...we're searching ponds, we're searching trash cans, we're searching everything."

Police say Braxton Williams is on the Autism spectrum but will communicate with others. 

Anyone with information on the children's whereabouts is urged to call JSO at 904-630-0500.