Security in the isolated desert region has deteriorated since the overthrow of President Hosni Mubarak in a popular uprising last February, the anniversary of which will be marked on Saturday. South Sinai's Red Sea coast is a major tourism hub for Egypt.

The Bedouin hostage takers, who complain of neglect from Cairo, want members of their tribe released from prison, the sources said.

The gunmen intercepted a tour bus travelling near the Saint Catherine monastery in central Sinai towards Sharm el-Sheikh. Twenty-seven other tourists were on the bus but were not taken. The youngest of the hostages was 51.

Earlier this month, two American women were held in a short-lived kidnapping until Egyptian authorities negotiated their release a few hours later.

Bedouin tribesmen in the Sinai have attacked police stations and blocked access to towns to show their discontent with what they see as poor treatment from Cairo, and to press for the release of jailed kinsmen.

Two dozen Chinese cement factory workers were kidnapped this month and released a day later in an incident Chinese officials said was isolated and would not impact their work in Sinai.

(Reporting by Yusri Mohamed in Ismailia, Writing by Dina Zayed; Editing by Peter Graff)

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