Freeing an entangled sea turtle hardly seems like a punishable offense. But according to officials, the rescue of a turtle by two Kennedy family members violated federal law.

While aboard Max Kennedy’s boat, he and brother Robert Kennedy Jr. dove into the Nantucket sea to rescue a 500-pound turtle whose head and fins were entangled in buoy line.

But according to the National Oceanic and Atmospheric Administration (NOAA) Division of Fisheries, the brother’s deed was “a violation of the Endangered Species Act .”

The organization has reacted by speaking with the Kennedy brothers and gathering “pictures, gear and other evidence involved in the rescue,” according to John Bullard, regional administrator.

Additionally, Bullard told the Cape Cod Times that the rescue was something “best left to the experts.” (SLIDESHOW: Turtles that look like Mitch McConnell)

“When we spotted a sea turtle in trouble over the 4th of July weekend, our first impulse was to do what we could to help free the animal,” Robert Kennedy said in the statement on NOAA’s website.

Robert Kennedy Jr. now expresses regret over the brother’s decision to save the turtle themselves.

“For both the animal and your own safety, we encourage any member of the public who encounters an entangled sea turtle or marine mammal to call NOAA Fisheries,” he said in an article on the NOAA’s website entitled “What Should You Do if You Encounter an Entangled Sea Turtle or Marine Mammal?”

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