Archaeologists believe that an ancient city from the Bronze Age was the site of terrible massacre, hiding hundreds of dead bodies in a mysterious mass grave, according to News United.

The city of Haft Tappeh, in relation to the Elamite Empire, was a city of "trade and art" that historians believed flourished more than 4,000 years ago.

But it appears that not all that glittered was gold in the ancient city.

In the ancient ruins, researchers found piles of bodies indiscriminately staked upon one another in a seemingly inhumane fashion, according to Mogaz News.

"Based on the number of skulls, we excavated 149 individuals," said Behzad Mofidi-Nasrabadi, an archaeologist from Johannes Gutenberg University. "In the unexcavated part of the trench, there should be another 100 to 150 skeletons."

The bodies, which included children, were hidden behind a wall.

The devastating incident, which brought the population to its knees, was thought to have happened about 3,400 years ago, and scientists can only speculate as to how or why so many people died, according to the Daily Mail. .

They say it could have been due to invasion or some sort of internal conflict.

The site is located in modern day southwest Iran.