(Adds details and background)
SANAA, Jan 10 (Reuters) - Militants linked to al Qaeda have released two South Africans kidnapped in the Yemeni city of Taiz in May last year, local officials and tribal sources said on Friday.
The man and woman were in good health, the local officials said, declining to give details of where they had been held or how they were released.
A security official in Taiz confirmed the couple had been released and said he had no information on the identity of the kidnappers.
Kidnapping of foreigners in Yemen is common, often carried out by disgruntled tribesmen seeking to press the government to free jailed relatives or to improve public services, or by Islamist militants linked to al Qaeda.
Yemen has been grappling with an Islamist insurgency which took advantage of unrest in 2011 inspired by the Arab Spring to seize control of some southern cities.
The insurgents were beaten back by government forces but have since regrouped and mounted attacks on government officials and installations.
Lawlessness in the poor Arabian Peninsula state has alarmed neighbouring Saudi Arabia, the world's leading oil exporter, as well as the United States, which increasingly views Yemen as a front line in its struggle against al Qaeda. (Reporting by Mohammed Ghobari; Writing by Rania El Gamal; Editing by Andrew Roche)