The family of Pierre Korkie who was kidnapped in the Yemen city of Taiz in May by Al-Qaeda militants have been praying for his release, but there is still no word from his captors, despite a deadline passing.

Pierre Korkie was kidnapped along with his wife Yolande in Yemen where the South Africans had been working as school teachers in a poor community.

The group that seized them was Al-Qaeda in the Arabian Peninsula (AQAP) which the United States regards as one the most dangerous affiliates of the jihadist group.

Yolande was freed in January with the help of a mediator from one of Yemen's powerful tribes and returned home.

But when South African Deputy Foreign Minister Ebrahim Ebrahim  traveled to Yemen to appeal for Pierre Korkie's release after that he returned home empty handed.

The 56-year-old Korkie is in poor health and his captors are demanding a ransom of $3 million (33 million South African rands) which is an enormous amount of money in South Africa.

Yolande Korkie, her children and extended family are anxious and out of their wits because the deadline for handover of the ransom was Saturday midday and has passed.

At that time they were to find out whether Pierre Korkie, their father and husband, was alive or whether al-Qaeda had carried out its threat to kill the teacher.

"It has been a crazy, crazy day. We are on a knife-edge. We hope we will know more tomorrow. We can talk tomorrow. But for now, we don't really have anything to say," a family spokesperson was quoted as saying in Johannesburg's Star newspaper on Saturday.

On Friday night religious leaders from different faiths in South Africa gathered at the Anglican Christ Church in Mayfair, Johannesburg to pray for Korkie's release.

The Johannesburg church was adorned with pictures of Pierre Korkie and was packed as South Africans of all religions prayed.

PLEA TO AL-QAEDA

Before the prayers began, on a big screen the church showed footage of his wife Yolande's desperate plea, which was sent to al-Qaeda, to release her husband.

"Pierre is an innocent and honest person who served the poor people through his teaching," said Yolande, sitting between her two teenage children.

"I wish to make it clear that the South African government did not pay any ransom money and Anas (al-Hamati) from Gift of the Givers did not receive any money.

"If he had received money our South African government would not have tolerated it, and we as a family regard Anas as a trustworthy and honest person.

"My husband is seriously ill and will not survive captivity."

Yolande and her two children did not attend the inter-faith prayer meeting, however she sent a personal message to those who attended the service.

The message read: "Pray for Pierre's release, for his health and for his mental frame of mind.

"Most of all pray for the mercy of al-Qaeda, so they see the light and release Pierre."

Leaders from the Muslim emergency relief organization, Gift of the Givers, said that although they haven't heard from the kidnappers in nearly two weeks, they believe that the group will make contact soon.

They said the captors will either contact them to reveal where Korkie will be released or to say where his body has been left after being killed.

Gift of the Givers negotiated Yolande's release on January 10 for no ransom, but al-Qaeda threatened to execute Pierre if they didn't get the $3 million ransom in eight days.