SANAA - Seven out of nine foreign hostages including a child were found murdered in northern Yemen on Monday, security officials said.

"We have found the corpses of seven people who were kidnapped," a local security official said. "They were killed."

Two of the three children captured with the group were reportedly found alive.

The bodies were found by the son of a tribal leader in Noshour, east of the volatile Saada mountainous area of northern Yemen where the nine were abducted, the official said.

The authorities had accused Shiite Zaidi rebels in Saada of seizing seven Germans, a British engineer and a South Korean woman teacher. The rebels denied the charge.

The nine -- among them three German children and two women nurses -- belong to an international relief group that has been working at a hospital in Saada province bordering Saudi Arabia for 35 years, a local official said on Sunday.

There was no immediate claim of responsibility for the kidnapping, the latest in a string of abductions of foreigners in one of the poorest countries in the world.

Seoul confirmed that a South Korean, identified by her family name Eom, 34, had been missing since Thursday evening in Yemen when she joined members of the relief group for a walk.

Local sources said the group was a Christian Baptist organisation that also has a medical team in the hospital at Jebla, south of Sanaa, where an Islamist militant killed three American doctors in December 2002.

In Berlin, a foreign ministry spokesman had declined to confirm that Germans had been seized, saying only that its embassy in Sanaa was in "close contact" with the Yemeni authorities.

A Yemeni official on Sunday said the group was taken hostage by members of the Huthi Zaidi rebel group which has been fighting the government since 2004.

A rebel spokesman dismissed the accusation as "baseless," and said the kidnapping took place in an area controlled by security forces in the town of Saada, in the centre of the rugged range.

Gunmen took hostage 28 foreign medical staff -- including Arabs -- from a hospital in Amran, north of Sanaa last Thursday and released them on Friday following tribal mediation, media reports said.

Huthi rebels were also blamed for that kidnapping.

"These staged kidnappings that we hear about these days are mere farces that would not fool anyone," said a statement issued later by the Huthi media office.

Foreigners are often kidnapped in Yemen for tribesmen to use as bargaining chips with the government over local disputes. More than 200 foreigners have been abducted over the past 15 years.

All have previously been freed unharmed, except for three Britons and an Australian seized by Islamist militants in December 1998 who were killed when security forces stormed the kidnappers' hideout.

In April, a Dutch couple were held for two weeks by tribesmen to pressure the government to pay compensation for an incident involving a tribal chief and security forces.