PORTLAND, Ore. (KOIN) — After numerous dives in an attempt to recover his body, authorities have officially named the man who is believed to have drowned in the Columbia River on Sunday.

Kevin McDowell, a 35-year-old man from Portland, went missing after reportedly jumping into the water to rescue a struggling swimmer, according to the Multnomah County Sheriff’s Office.

Officials say McDowell jumped from a boat into the Columbia River near the west end of Lemon Island to help a woman that was having a difficult time trying to swim. The woman was able to get to safety — but McDowell never resurfaced.

Deputies from the River Patrol Unit went to the scene along with boats from Portland Fire & Rescue and the Coast Guard. However, officials said that an extensive search did not find him.

On Monday, the Multnomah County Sheriff’s Office River Patrol Unit and Dive Team performed additional searches for McDowell. But with “limited underwater visibility and strong currents,” McDowell’s body wasn’t located.

The sheriff’s office says marine deputies will perform additional searches when the call volume allows.

A GoFundMe has been created on behalf of McDowell’s family.