After he found it, he called the police who opened it.
"Then the cops came down and opened it up partially, and there was like, blood," Cerulli told WCVB. "Couple layers and there was a duffel bag, but there was like four or five layers to the bag. It was like a tarp."
The body was found to be that of a black man, 5 feet 10 inches to 6 feet tall, approximately 230 pounds with a 4-inch surgical scar on his abdomen.
The only clue they have to what might have happened is a shirt that was still wrapped around the abdomen.
"They told us the shirt was probably 6 to 8 years old. They gave out thousands over the years to customers and vendors. We want to know whether members of the public might have seen someone wearing a shirt like that over the past few days," said District Attorney Michael D. O'Keefe.
Police designated the beach as a secondary crime scene, saying the victim was killed elsewhere. The body is believed to have been there two days at most.