A shark killed a seal Monday off the coast of Nauset Beach on Cape Cod, causing it to close.
The attack happened near two surfers, prompting beach-goers to panic, thinking a person had been attacked.
The beach, located in Orleans, Massachusetts, was closed for some time.
Surfer Nisi Schlinger, of Brookyln, New York, described seeing a "seal, half eaten, bleeding — blood everywhere."
"I felt like the shark's gonna pull me in from my legs or something," Schlinger continued. "People [were] yelling, 'Get out the water! Get out the water!' I thought I was dead."
Schlinger was with his friend Zevi Greenspan. It was the first time either had gone surfing.
The teens were so busy on their surfboards, they were oblivious to what was going on onshore.
"I see people running, people screaming and running and I thought the eclipse so I look up at the sky I couldn’t find it," said Schlinger.
"I look on the left and I see my friend Nisi paddling for his life and I see something flubbering in the water with blood all around it. I thought it was a person," Greenspan said.
The teens swam to safety but said they will think twice about returning to the water.
"For me to go near water again, it’ll take some time," said Schlinger.