Amateur photographer Thomas Vijayan captured the striking moment when two enormous bears brawled in the shallow water of a clear river in the wilderness of Katmai National Park, Alaska, USA. The huge 4,000-pound predators roared aggressively as they splashed and wrestled in the cold water.

The Katmai National Park is known for its bears and its volcano-devastated region. It's an important habitat for salmon and thousands of bears that feed upon them. 

(All photos via VCG)

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