Matt Leffers was bitten by otters at least 12 times while swimming at Serene Lakes in California. Leffers has been swimming there for 30 years, and never experienced anything like this.
"These things were so aggressive that, literally, I felt like they wanted to kill me," he said. Leffers' wife saved him using a paddleboat and took him to the hospital.
Peter Tira of the California Department of Fish and Wildlife said that while otter attacks are rare, they defend their territory if they feel threatened.
Wildlife officials are working to confirm the number of otters in the area.
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