Yemeni security officials say at least seven of the nine foreigners kidnapped in a northern mountainous region have been killed.
Officials said Monday local residents found the bodies of three women near the town of Nashour. Two are reported to be German and one South Korean.
Later in the day, authorities said they had discovered the bodies of at least four more hostages. Their nationalities were not immediately clear, but authorities said all of them were among the group of seven Germans, a British engineer and a South Korean teacher taken hostage in the Saada region last week.
Government officials on Sunday accused a Shi'ite rebel group of kidnapping the foreigners. The rebels deny any involvement and accuse the government of trying to tarnish their image.
The grisly finds came a day after Yemen arrested a Saudi man, Hassan Hussein bin Alwan, suspected of being al-Qaida's top financier in Yemen and Saudi Arabia.
The kidnapped group is said to include three children, two nurses and an engineer and his wife. They were reported to be working at a hospital in Saada.
Tribesmen in Yemen often take foreigners hostage to pressure the government on a range of demands, but those foreigners are generally released unharmed.
The German Foreign Ministry says it has not confirmed the deaths of the hostages.
South Korea's Foreign Ministry previously identified the missing South Korean only as a 34-year-old woman with the family name Eom.