A man was arrested and was being questioned by authorities in connection with the killing, the security source said.

"We do not want to predict the result of the investigations ... and whether or not the criminal's motives were political or not," he told Reuters.

There are an estimated 200 to 300 Jews in Yemen, remnants of a community that spoke a form of ancient Hebrew as a living tongue. About 50,000 moved to Israel thanks to an airlift begun in 1949.

Sunni Muslims make up the majority of Yemen's 19 million inhabitants, while most of the rest are from the Zaydi branch of Shi'ite Islam.

Yemen, the ancestral home of al Qaeda leader Osama bin Laden, has been battling Islamic militants for years and has grappled with a spate of attacks on Western targets this year, including two on the U.S. embassy.