“We suggested that the reason [for] this opened mouth could be due to [a] painful death or emotional stress and cadaveric spasm made her face frozen to the appearance at time of death,” said Saleem. “Embalmers were unable to close the mouth and mummified the contracted body before it decomposed or relaxed, preserving her open mouth after death.”

However the cause of death remains unclear, while the researchers note other experts have proposed a screaming expression could be the result of burial procedures or changes after death.

While rare, the woman is not the only “screaming” mummy. Saleem and colleagues have previously studied the corpse of what is thought to be Prince Pentawere, the son of Pharaoh Ramesses III who was involved in a plot to kill his father.

“Pentawere’s body was barely embalmed, which may indicate that the embalmers neglected to keep his mouth closed likely as a punishment causing him to scream for eternity,” said Saleem.

The remains of Princess Meritamun, thought to be the sister of King Ahmose, who ruled from about 1550 to 1525BC, also has such an expression.

Saleem and colleagues say their previous work suggests Meritamun died of a sudden and massive heart attack. “The widely opened mouth was likely natural postmortem jaw drop that was maintained due to a postmortem muscle contraction – rigor mortis – that prevented embalmers from closing her mouth,” said Saleem.