INDEPENDENCE, Ore. -- The bodies of the two brothers who disappeared while fishing in the Willamette River Sunday have both been found, investigators on the scene told KGW.

Police said Alvin Troub's body was found around 1 p.m. Tuesday, submerged in the high water near a dock. His little brother's body was found almost an hour later, in the water nearby.

The brothers, 20-year-old Alvin and eight-year-old Michael Runyon were last seen Sunday fishing on the Willamette River banks in Independence.

Polk County authorities had changed the search effort from rescue to recovery on Tuesday, after clues kept pointing them to the likely drownings.

On Monday, water scent dogs marked two places in the river. A dive team from the Linn County Sheriff's Office dove in one of these areas but found nothing. They said visibility in the river was less than a foot, making searching very difficult.

Then, Tuesday morning, three new water scent dogs were brought to the riverside and they also marked a location near the area where the different set of dogs had alerted their trainers the day before.

 Slideshow: Photos of brothers

On Sunday and Monday, search crews used boats, divers and cameras along with dogs, helicopters and volunteers to try and find the two boys.

Mary Troub, the boys’ mother, said Michael cannot swim and feared that was “very, very scared.” She also said that Michael was diagnosed with autism.

“They're extremely close," Mary Troub told KGW on Monday. Alvin's like a role model to Michael. He loves him to death.”

Authorities at first found the boys' fishing equipment yards away from the river, but no sign of them.

Family members spread the boys’ pictures that were plastered on flyers in store-front windows from Independence all the way to Monmouth.

"We just can't figure it out, [the boys' mom] was thinking someone may have taken the boys, but Alvin is such a big boy," said their aunt, Laurie Runyon. "Alvin takes really good care of his fishing poles. I don't know what's going on.”

KGW Reporters Mike Benner and Erica Heartquist contributed to this report.