A soldier accused of having an affair with a local woman has been stoned to death on the orders of tribal elders in north-west Pakistan, officials say.

Elders in Kurram tribal agency said scores of people threw stones at the soldier in a cemetery near the town of Parachinar until he bled to death.

Locals in the mostly Shia area opposed the alleged relationship because he was a Sunni Muslim and the woman a Shia.

There was no immediate response from the military.

Sunni and Shia Muslims Muslims are split into two main branches, the Sunnis and Shias

The split originates in a dispute soon after the death of the Prophet Muhammad over who should lead the Muslim community

There are also differences in doctrine, ritual, law, theology and religious organisation

The great majority of Muslims are Sunnis

Pakistan - where Shias are a minority - has a history of sectarian bloodshed dating back to the 1980s Pakistan's evolving sectarian schism Formidable power of anti-Shia militants

The BBC's M Ilyas Khan in Islamabad says it is not uncommon for those deemed to be involved in illicit relationships to be shot in Pakistan, but few if any public stonings have been carried out.

Shias in Pakistan are angry over the high number of sectarian attacks against them across the country in recent months.

Last year more than 400 Shias were killed in Pakistan by Sunni hardliners. So far this year, more than 200 Shias have been killed.

Warnings

Officials say that the soldier, Anwar Din, was detained by villagers near Parachinar after attempting to see the woman. Her family consulted tribal elders in the town who ordered that he be stoned. The sentence was carried out on Tuesday.

"The girl left her home on Monday and met Anwar Din when villagers saw them," tribal elder Munir Hussain told the Reuters news agency.

"We took the girl into custody and took the boy to the local graveyard where he was stoned to death and buried."

Mr Hussain said that elders had requested that another Pakistani soldier be handed over by the army for helping the couple meet and co-ordinate their planned elopement.

"The army is here for our security but if they engage in such activities we will not let them stay here," he said. "This is an insult to tribal customs. We will revolt against this."

Image caption Kurram's population is predominantly Shia

The villagers were also angry because the soldier - who reportedly began the relationship when his army unit was based in Kurram - persisted with the alleged love affair even after his unit had been redeployed and despite numerous warnings from villagers not to do so.

At the time of his death, officials say the soldier - from Punjab province - was in the Kurram area in a private capacity. He had reportedly kept in touch with the woman by telephone.

Punjabis are especially disliked by many in Kurram, our correspondent says, because they are seen as being at the forefront of sectarian hatred towards Shias.

Kurram is in Pakistan's Federally Administered Tribal Areas, which have never been fully integrated into the country's administrative, economic or judicial system.

Instead, tribal elders often take the law into their own hands, dispensing punishments for crimes including rape and murder and in cases where a family's honour is seen to have been impugned because of an illicit relationship.