Archaeologists have unearthed a mass grave next to an ancient temple in Egypt that once contained nearly eight million mummified dogs and puppies.
Ancient Egyptians built the temple and catacomb in honour of Anubis, the jackal-headed God of death, in Saqqara, a burial ground in the country's ancient capital of Memphis.
The catatomb may have once held nearly eight million mummified puppies and grown dogs, researchers have estimated.
Many of the mummies have since disintegrated or been disrupted by grave robbers and industrialists, who likely used the mummies for fertiliser.
Paul Nicholson, a professor of archaeology at Cardiff University in the UK studied the catacomb's rock walls and mummified contents. The catacomb was likely built in the fourth century BC, and was made out of stone from the Lower Eocene (about 56 million to 48 million years ago).
In addition to canine mummies, researchers found the mummies of jackals, foxes, falcons, cats and mongoose, although about 92% of the remains belonged to dogs, 'Live Science' reported.
"It's unclear why these other animals were buried in the dog catacomb, but it is likely that all 'doglike' creatures were interchangeable, and that mythological reasons probably underlie the choice of cats and raptors," the researchers wrote in a study published in the journal Antiquity.
Many of the dogs were only hours or days old when they were mummified. Some older dogs had more elaborate burials, and may have lived at the temple, but the younger pups were likely "bred - farmed if you will - for the cult," Nicholson said.
It's likely that these young pups were separated from their mothers and died from dehydration or starvation.
"They probably weren't killed by physical action; we don't have evidence of broken necks that you get with cat burials," Nicholson said.
The catacomb ceiling also contained the fossil of an ancient sea monster, a marine vertebrate that is more than 48 million years old.
"The ancient [Egyptian] quarry men may have been aware of it, or they may have gone straight through it, it's hard to know," said Nicholson, who is researching the fossil with his colleagues.