Jihadist group Ansar Bayt al-Maqdis on Tuesday claimed the suicide bombing in Egypt of a tour bus that killed three South Koreans and their local driver.

“One of the heroes of Ansar Bayt al-Maqdis carried out the attack on a tourist bus heading towards the Zionist entity (Israel),” said a statement attributed to the group and posted on jihadist forums.

The group said in the statement that one of its “heroes” carried out Sunday’s bombing on the Egyptian side of the Taba border crossing into Israel as part of an “economic war” against Egypt’s army-backed government.

Egyptian officials have called it a suicide attack, but the Ansar statement did not use any language that would suggest the perpetrator was dead.

The al-Qaeda-inspired group has claimed responsibility for previous attacks, but until now they have targeted primarily police and the military.

The authenticity of the statement could not be verified but it was posted on al-Qaeda-affiliated websites.

The bombing on Sunday was the first targeting tourists since the military overthrow of Islamist president Mohamed Morsi in July sparked a militant campaign that has killed scores of police and soldiers.

The blast killed the bus’s Egyptian driver and three members of a Korean Christian tour group, injuring 13 more. The group had been about to cross into Israel when the explosion occurred.

South Korea condemned the attack, calling it “beyond deplorable,” and vowing to combat terrorism, the Yonhap news agency reported.

The attack threatened to sink tourism in a region that has kept the industry alive even during the political turmoil wracking the country — the beach resorts of the Red Sea in the Sinai Peninsula. Those resorts on Sinai’s eastern and southern coasts, a favorite of divers and Europeans escaping the winter, had seemed a world away from the political unrest in the Nile Valley, and even from the wave of Islamic militant violence on Sinai’s northern Mediterranean coast.

The Islamist group reportedly threatened to continue attacks against tourists later in the week, giving visitors four days to leave the peninsula, Israel’s Channel 2 news reported Monday.

The hit comes as Egypt’s tourism industry is trying to bounce back. In 2010, the sector was one of the most powerful engines of the country’s economy, bringing in more than 14.7 million tourists and some $12 billion in revenue. It employed around 13 percent of the workforce and raked in a fifth of Egypt’s foreign currency.

The 2011 revolt against president Hosni Mubarak, and the ensuing instability, hit it hard: That year, visitors dropped to 9.6 million, earning the country $8.8 billion. In 2012, the industry slowly clawed back, with around 10.5 million tourists coming.

Last year, however, saw the ouster of Morsi and escalating violence as authorities cracked down on his Muslim Brotherhood, and visitors dropped to 9.5 million, fewer even than 2011. The large majority of those tourists — nearly three-quarters of them — stuck to the Red Sea resorts.

Still, even south Sinai has felt the blow. In Sharm el-Sheikh, Sinai’s main Red Sea resort, about 100 miles (160 kilometers) south of Taba, occupancy at the city’s hotels is currently averaging around 45 percent, but most guests are Egyptians enjoying vastly discounted rates, according to tourism workers.

Adel Shokry, manager of a luxury hotel there, sought to play down the likely impact of Sunday’s bombing, arguing that past attacks have had short-lived impact on tourism in Sharm.

“I believe the attack will not gravely affect tourism … and things will go back to normal,” said Shokry.

Egypt’s militants targeted tourists in the 1990s, trying to cripple the economy as they waged an insurgency to topple Mubarak’s government. Security forces ruthlessly crushed the campaign by the end of the decade.

The last major attacks on tourists came in a string of militant bombings against resorts in southern Sinai — including in Taba — between 2004 and 2006, killing about 120 people. But the tourism industry quickly rebounded.