Reports that a British man was among nine foreigners who were kidnapped last week by suspected al-Qaeda-linked terrorists were deeply concerning, the Foreign and Commonwealth Office said, after it emerged that some of the group had been killed.

British officials are seeking urgent clarification from Yemeni authorities after conflicting reports of the hostages’ fate. The group comprised a British engineer, his South Korean wife and seven Germans, who were abducted in northern Yemen on Friday while picnicking in the mountains. Three of the Germans are children.

Last night Yemeni officials confirmed that three women — two Germans and a South Korean — had been killed. “We have found the corpses of three women . . . who were kidnapped alongside six others,” an Interior Ministry official said. The bodies were reportedly found by shepherds in the northern province of Saada, where Shia separatist rebels have previously kidnapped foreigners for political aims or ransom, but where the murder of hostages remains rare. The main rebel group in Saada has denied responsibility, blaming the abductions and killings on al-Qaeda militants.

In the United States, the CIA has been tracking a growing influx into Yemen and Somalia of al-Qaeda fighters from Pakistan, where they are coming under growing pressure from US and Pakistani military action.

The only hostage to have been identified is the South Korean woman, a 34-year-old aid worker whose family name is Eom. “We are very concerned that bodies were found,” a British Embassy spokeswoman said. “We are seeking further details.”

Reports from Sanaa said that at least two of the Germans had been working as medical staff at a hospital. The South Korean woman is said to have been working as a teacher. The German family may have been visiting Yemen.

The events, a day after the Yemeni authorities arrested the man believed to be al-Qaeda’s top financier on the Arabian Peninsula, are a dramatic increase in political violence in the region. Confusion is widespread, especially as there has been no effort to maximise the propaganda potential of nine foreign hostages or to exact a political price for their return.

Al-Qaeda militants have found sanctuary among a number of Yemeni tribes along the border with Saudi Arabia. In January militants announced the creation of al-Qaeda in the Arabian Peninsula, a merger between the terror network’s Yemeni and Saudi branches, led by Naser Abdel-Karim al-Wahishi, a Yemeni who was once a close aide to Osama bin Laden.

Al-Qaeda has been blamed for a series of attacks over the past year, including an armed assault in September on the US Embassy in Sanaa and two suicide bombings against South Korean visitors in March. Yemen, bin Laden’s ancestral homeland, has produced many of al-Qaeda’s officials. It was the location for one of the organisation’s most high-profile attacks before September 11, 2001 — the bombing of the USS Cole.

Yemenis are the largest single national group among detainees in Guantánamo Bay classed as too dangerous for unsupervised release. The US is unwilling to allow them home because of concerns about the Sanaa Government’s ability to imprison them or monitor militant activity. Yemen lies just across the Gulf of Aden from Somalia, where the CIA says hundreds of al-Qaeda militants have arrived recently.

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