A mentally challenged woman on Monday allegedly stoned to death a pillion rider on top of the Kwame Nkrumah Interchange, in Accra.

The deceased, yet to be identified, was on a moving 'Okada' on one of the interchange levels when the woman struck him with a stone.

"The man died before passersby arrived at the scene, an eyewitness said.

The unknown man was seen lying in a pool of blood with a large stone near his right hand.

.According to the eyewitness, when the victim fell off the motorbike, the woman pounced on him and attacked him with the large stone.

Police later apprehended the woman after a mob had threatened to lynch her.

She was handcuffed and transported in a police pickup truck, escorted by three officers to a pickup and taken to safety.