People in drought-ridden Tunisia have been enjoying a respite from the scorching heat after a "miracle" lake appeared in the middle of the desert. Hundreds of locals flocked to what has become known as Gafsa beach after shepherds stumbled across the mysterious expanse of water three weeks ago.
Experts suspect seismic activity may have ruptured the rock above the water table sending the liquid to the surface.
However, despite warnings the water may be contaminated or even radioactive, Tunisians have descended on the impromptu "beach" in force to escape the 40C heat.
"Some say it is a miracle, while others are calling it a curse," Lakhdar Souid, a Tunisian journalist, told France 24 television.
"In the first few days, the water was crystal clear; a turquoise blue. Now it's green and full of algae, which means it's not being replenished."
The Gafsa region of central Tunisia is home to the country's mining industry and phosphate was first discovered in 1886.
The fear is that the "Lac de Gafsa" is full of chemicals, and the algae will give rise to disease.
"News of the lake's appearance has spread like wildfire and now hundreds of people, eager to escape a heatwave, go there to swim," Souid wrote in the Tunisia Daily newspaper.
"The site is certainly stunning and there are many large rocks perfect for diving, but it has become infested with green algae, meaning the water is stagnant and conducive to diseases.
"This lake is located in an area rich in phosphate deposits, which leave residue that is sometimes strongly radioactive.
"So there is a real risk the water is contaminated and carcinogenic."