FORT JENNINGS — A search is focused on the Auglaize River for a 5-year-old boy with autism.

Isaac Schroeder, 5, who has non-verbal autism, has been missing since around 3 p.m. Wednesday. He is average build with short, blonde hair, according to the Putnam County Sheriff’s Office. Schroeder was wearing only Thomas the Train underpants at the time. He knows his name, according to a Facebook post by his mother.

Capt. Brad Brubaker of the Putnam County Sheriff’s Office provided an update on the case at 10 a.m. Thursday. He said they’re concentrating on the Auglaize River because of its

More than 300 volunteers arrived in Fort Jennings by 7 a.m. today to help search for the child. They combed through the area looking for the boy despite a downpour of rain hampering their efforts. Additional people can help by going to the Fort Jennings Park’s shelter house to sign up to help, where they’ll be deployed in groups.

Officials asked people with kayaks and canoes to stay away from the river.

Brubaker said helicopters with infrared heat sensors are ready to deploy but haven’t been allowed out yet because of the rainy weather.

The sheriff’s office received a 911 call from the boy’s mother, Sarah Schroeder, at 3:09 p.m. Wednesday. Brubaker said the child likely left his home through a garage door.

Deputies, police, EMS and fire crews searched along the Auglaize River on Wednesday afternoon and night without finding the boy.

Crews reminded volunteers to stay in groups of at least two people and have cell phones with you. They urged people to stay away from the river and wooded areas after dark so no one gets lost or injured.

Dive teams and boats from the Continental Fire Department, Delphos Fire and Rescue, American Township in Allen County and Allen Township in Hancock County assisted in water searched. Other agencies who assisted in the search included the Ohio Department of Natural Resources, Ohio State Patrol and LifeFlight.