A mystery black substance that appeared on a beach turned out to be millions of dead insects, it has been reported.
Experts investigated after reports were made of the bizarre sight on Wells Beach in Maine, USA.
Locals had noticed the strange dark substance that stained the feet of beachgoers before reporting the peculiar situation, The Mirror reports.
Ed Smith, who has walked the beach for years, told local media he had never seen anything like it.
He first noticed the sight on Sunday and said that dozens of other locals had also noticed the strange appearance, which stained people’s feet.
The Portland Press-Herald reported that Steve Dickson, a marine geologist with Maine Geological Survey, made a grim find and discovered that the black substance was in fact the “collective carcasses of millions of dead insects”.
He said he had never seen anything like it in his long career.
Mr Dickson said: “This is the first time I’ve seen or heard of this in my 35 years.
“Normally this time of year we get calls about too much seaweed (wrack) on the beach and the swarming flies that hang around the decaying seaweed. This wasn’t that.”
Experts are still trying to figure out what the bugs are, and where they came from and why.
Mr Dickson said that he does not expect it to be a recurring phenomenon and that the bug debris left behind is likely to wash back out to sea.
He added: “You never know what nature is going to bring next.”
Married couple Linda Stathoplos and John Lillibridge, who live nearby and are retired oceanographers, have been drafted in to solve the mystery.
Linda said: “I collected some of the stuff, brought it back and put them under my microscope. It was clearly little bugs.”