A BRITISH engineer kidnapped in Yemen by armed killers was part of an evangelical group that may have been targeted as an act of revenge for its attempts to convert local Muslims to Christianity.

His captors have already killed three women members of the group and abducted a married couple and their three young children.

Yesterday, as his wife clung to the hope that he was alive, it was reported that two of the dead women – Anita Gruenwald, 24, and Rita Stumpp, 26, both German nurses - had “missionary materials” in their belongings when their bodies were found. Young-Sun Lum, 34, a South Korean teacher who called herself Magdalena after Jesus’s disciple, was the other victim.

They had been warned to stop trying to convert Muslims, according to German investigators. Mullahs had spoken out against their missionary activities and their books on Christianity had been confiscated.

They had been on an outing from the hospital where they worked in Saada, near the Saudi Arabian border, when they were attacked.

The search for survivors has become a race against time in the harsh terrain. Johannes Henschel and his wife Sabine, 36, a German couple, have their three children - Lydia, 4, Anna, 3, and Simon, an 11-month-old baby - with them.

Yesterday there were reports that the kidnappers’ car, a black Suzuki Grand Vitara, and the victims’ Toyota 4x4 had been spotted.

Yemeni troops have been searching the region 150 miles from Sana’a, the capital, on foot and by helicopter since Monday, when child shepherds found the bodies of the two Germans and the South Korean woman in a riverbed while tending their animals. The authorities have offered a $275,000 (£150,000) reward for information.

Initial reports said the three victims had been shot and stabbed. Hamboush Hussein, general director of the local health office, said they had not been mutilated but had several gunshot wounds in the head, chest or back as if they had been struggling and trying to escape.

Britain has sent a team of counterterrorism experts to Sana’a because of the possibility of Al-Qaeda involvement. While the investigation continues the Foreign Office has imposed a virtual news black-out, withholding the British engineer’s full name. In Yemen he has been identified only as Anthony.

All the victims were members of Worldwide Services, a Christian relief group based in Holland that has been working at al-Jumhuri hospital in Saada for 30 years.

Worldwide Services is connected to a British evangelical organisation called WEC, believed to stand for Worldwide Evangelisation for Christ. Its website says its mission is to “reach the remaining unreached peoples of the world with the good news of Jesus, to plant churches where there is no church”.

On Friday, June 12, their day off, the group drove to visit a relative of one of the hospital staff who was recovering from a kidney operation. According to German investigators they stayed until 6pm. Witnesses said that on their way back their vehicle was intercepted by armed men.

At 6.45pm one of the two young German women managed to call another nurse working at the hospital who has been named only as Rosa. The connection was bad and the woman hung up.

A war has been raging intermittently in the area since 2004 between a minority Shi’ite rebel tribal group called the Huthis and government forces.

But by the end of last week German and British investigators had largely discounted Huthi involvement and saw the kidnapping and killings as more suggestive of Sunni extremists, increasing the fears of an Al-Qaeda resurgence in Yemen.

However, Faiz al-Awjari, an MP and a member of the security committee in charge of the investigation, said there were still some indications of Huthi involvement. The kidnappers’ and victims’ vehicles had been sighted in Matarah,a Huthi stronghold, but the Huthi were denying access to the government authorities.

The Huthi claimed that the kidnappings had occurred in a government-controlled area. On Wednesday they staged a public demonstration to denounce the killings.

The kidnapping of foreigners is common in Yemen, where tribes often use them as bargaining counters with the government in local disputes. More than 200 foreigners have been abducted over the past 15 years but only a handful have been killed or injured.

“This kidnapping was the first time that hostages were killed straight away and it is a worrisome development,” said Christopher Boucek, a Middle East terrorism expert for the Carnegie Endowment for International Peace in Washington.

In February, a month after Al-Qaeda in Yemen merged with its Saudi Arabian counterpart, Dennis Blair, America’s director of national intelligence, had identified the country as a potential new haven for the group.

“Yemen is re-emerging as a jihadist battleground and potential regional base of operations for Al-Qaeda to plan attacks, train terrorists and facilitate the movement of operatives,” Blair said.

Yemen, the Arab world’s poorest country, suffers chronic social and economic problems. The war between the Huthis and the government in the north is mirrored by a secessionist movement in the south. The country is running out of both oil and water.

Western security experts fear the growing poverty and instability can only fuel Al-Qaeda militancy. Last year an explosion at the US embassy in Sana’a killed 16 people, none of them Americans.

In March four South Korean tourists visiting a Unesco World Heritage site in eastern Yemen were killed by a teenage suicide bomber. A Yemeni tour guide also died.

Break-out

An American journalist kidnapped by the Taliban has escaped after seven months of captivity in Afghanistan and Pakistan.

David Rohde, of The New York Times, was abducted with an Afghan reporter and their driver outside Kabul last November.

He told his wife that he and the other journalist, Tahir Ludin, had climbed over the wall of a compound where they were being held in northern Pakistan.

The men found a Pakistan army scout nearby who led them to a military base.

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