LEETSDALE, Pa. (KDKA) — Search efforts continued Tuesday as officials hope to locate a 10-year-old boy who fell into the Ohio River in Beaver County.

On Monday, emergency crews were in the area between the Ambridge Sewage Treatment Plant and the Leetsdale Boat Ramp at the Ohio River.

“Family did not know they were down here. They were supposed to be out riding bikes,” Lt. Brian Jameson, of the Ambridge Police Department, said.

The 10-year-old boy is believed to have slipped in the water near Route 65. He was with a group of kids, ages 8-13.

It’s now a search and recovery mission as the boy is believed to have drowned, first responders say.

Today, teams are using sonar on their boats to try and find him. Dive teams were also called in to check the river.

(Photo Credit: KDKA Photojournalist Aaron Sledge)

First responders say one brother tried to grab the other after the child lost his shoe and couldn’t get it back.

“He hit the drop off and slid down in. His brother went out into the water and was able to grab a hold of him. They tried to pull him back in, and his grip slipped and he never resurfaced after that,” said Lt. Jameson.

According to Beaver County emergency officials, the 10-year-old boy is about four-and-a-half feet tall and has a light complexion. He was wearing a Mickey Mouse t-shirt and green shorts.

WATCH: KDKA’s Pam Surano Has More From The Scene

For hours on Monday, rescue crews and dive teams searched by air, water and ground to find him.

Three dive teams and six fire departments, along with the state police helicopter conducting low flyovers, were also on the scene.

“They weren’t able to pick up anything. So we’re pretty much relying on the divers to come up with something,” said Chief Rob Gottschalk, of the Ambridge Fire Department.

(Photo Credit: KDKA Photojournalist Aaron Sledge)

So far, there are no signs of the 10-year-old boy.

The initial report came in around 2:45 p.m. Monday

“If you’re going to be going down here close to the river, go down with an adult,” Chief Gottschalk said.

The fire chief say they hope to find this boy so they can give closure to the family during this tough time.

Crews will resume the search on Wednesday morning as the child has not been found.

The state police are bringing in special equipment.

Stay with KDKA for the latest on this developing story.