Two other mummies were wiped out in the 1941 bombing of Leeds' museum – leaving the city without a permanent museum ever since – but Nesyamun escaped unscathed.

And the story behind his demise was revealed as a major operation got under way to move Nesyamun to the new £20m Leeds City Museum in Millennium Square, where he will be one of the star attractions when it opens on September 13.

Mountain rescue equipment had to be called in to move the mummy from Leeds Discovery Centre, where it has been undergoing restoration, to the museum.

In studying Nesyamun curators have come to the conclusion that a simple sting from a small bee or other insect could have caused his death.

The venom is thought to have caused an allergic reaction, killing him rapidly.

His perfectly-preserved face is contorted in a way which is consistent with a sudden, dramatic death, with the eyes bulging and– very rare for mummies – tongue protruding.

Embalmers would always close the mouth and not do so is an indication they were unable to.

Also going on public display is a striking reconstruction of Nesyamun's head, which depicts him in a startling and very lifelike manner as he would have looked as a priest in Thebes 3,000 years ago.

It was produced by renowned medical artist Richard Neave, of Manchester University, using information obtained following a 360-degree scan of the mummy's head.

Visitors will for the first time be able to see Nesyamun's face. His hands and feet will also be visible, with the rest of his body loosely covered by linen bandages.

His ornate coffin lids will also be in the climate-controlled case with him, which are covered in prayers for his safe passage to the afterlife written in Egyptian hieroglyphs.

The council's curator of archaeology, Katherine Baxter, said: "It is possibly quite controversial to display the mummy himself at a time when other museums are debating whether it is best to cover them up.

"We have thought long and hard about this and we feel we learn far more about him as a person this way.Our reconstructed tomb is towards the back of the gallery and designed so you have to make a conscious decision to go in and look at him. That's far more respectful than putting him in a glass case."

Nesyamun was brought to the city by local banker John Blayds, who bought the mummy in 1823 for the Leeds Philosophical and Literary Society.

l Don't miss five days of special features on the museum in next week's YEP.