TAMPA, Fla. (WFLA/NEXSTAR) — A Florida man died after being buried alive when a sand dune collapsed on him as he recorded the sunrise early Sunday, authorities said.

A beachgoer checking on sea turtles south of the House of Refuge on Hutchinson Island called for help after spotting a pair of feet jutting out of the sand, Martin County Sheriff’s Office Public Information Officer Christine Weiss told Nexstar.

The feet belonged to a Stuart man identified as 37-year-old Sean Nagel, who died when the dune behind him collapsed, according to MCSO investigators. After some investigation, detectives determined that the man’s death was accidental.

“It appeared that where the dune was, he dug a little space out of that dune and sat into it,” Weiss said.

He was using a GoPro camera to record the sunrise, something family members said he often did, when the dune collapsed on him, according to Weiss. The camera was found at the scene, pointed out toward the ocean.

“It appears that the man died … from asphyxia as a result of being trapped underneath the sand,” the sheriff’s office said in a news release Monday.

There was no trauma to the body and no signs of foul play.

“Investigators are awaiting toxicology tests, which is standard,” the sheriff’s office said. “Those tests, however, are not likely to change the outcome of this incident being a tragic accident.”