A 23-year-old man who fell into the Yukon River Wednesday is believed to be dead after his boat struck a log near Emmonak, according to Alaska State Troopers.

Word of the incident involving Dennis Westlock reached troopers at about 12:30 p.m. Wednesday, troopers said in an online dispatch. Another 23-year-old Emmonak resident, Brandon Johnson, was rescued by a fellow boater who saw the collision.

The witness, 27-year-old Darren Jennings, told troopers he saw a “large splash” and immediately approached to assist.

“Jennings observed the boat was empty and he saw two people in the river,” troopers wrote. “Jennings immediately pulled [Johnson] into his boat but when he turned to find the second person he was unable to locate him.”

Johnson was treated at the Emmonak clinic for hypothermia, troopers said.

“Westlock has not been located and is presumed drowned,” troopers wrote. “Westlock’s next of kin are reportedly on scene.”

Recovery efforts to find Westlock were continuing Thursday.

Asked if Johnson and Westlock were wearing personal flotation devices, troopers spokeswoman Megan Peters said they were on hand but not used.

"No -- they were sitting on the life jackets," Peters wrote in an email. "[Search efforts], like dragging the river, are ongoing by local volunteer searchers."

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