Burgas is a quiet resort around 250 miles east of the capital Sofia on the Black Sea coast.
It is popular with Israeli tourists as a cheaper alternative to other Mediterranean resorts, especially for recent high school graduates before they are drafted for mandatory military service.
Although no-one has claimed responsibility for the attack, some believe Bulgaria poses a greater risk to Israeli tourists because of the shared border with Turkey.
Bulgaria's President Rosen Plevneliev was quoted as saying that the attack "does not mean that Bulgaria is a risky destination for tourism".
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