More than 300 dead, along with some 120 injured, all of them people taking part in Friday prayers. Just as the worshipers were leaving the mosque, terrorists detonated the bombs they had previously laid around the building, and then opened fire on those who fled.

So far, no one has taken responsibility for the attack in Bir al-Abed, some 40 kilometers (25 miles) south of the provincial capital, Arish. But according to media reports, the Egyptian state prosecutor entrusted with the investigation into the attack has said that the assailants were carrying the flag of the jihadi organization "Islamic State" (IS).

The Egyptian air force responded by carrying out strikes in Sinai, bombing suspected terrorist hideouts. The spokesman for the Egyptian armed forces, Tamer al-Rifai, wrote on his official Facebook page that warplanes destroyed several vehicles overnight that had been used in the attack on the mosque in Bir al-Abed.

It is widely believed in Egypt that the mosque was targeted because Sufi Muslims worshipped there. The Egyptian Supreme Council for Sufi Orders announced late on Saturday that they plan to proceed with an annual celebration in Cairo to mark the birthday of the Prophet Mohammed, despite the attack.

Read more: Sufi Islam: What you need to know

Bedouins as second-class citizens

The Sinai Peninsula has been the scene of jihadi attacks for a number of years now. In 2014, a suicide attack there killed 33 soldiers. In response, President Abdel-Fattah el-Sissi imposed martial law on the region. During the following years, the conflict between the army and terrorists grew in intensity; both sides suffered major losses in clashes.

According to the political scientist and journalist Asiem El Difraoui, a major cause of the violence in northern Sinai is the economic and cultural situation of the Bedouins who live there. He says that their difficult position gives IS ideological leverage.

"The Bedouins have always been seen as second-class citizens. They live under difficult economic conditions and are disparaged as criminals and smugglers," Difraoui told DW. "They receive no benefit from the wealth generated in Sinai from oil and tourism."

Golden memories of Israeli occupation

The social geographer Günter Meyer, who heads the Center for Research into the Arabic World at Mainz University in Germany, has been conducting field studies on the Bedouins' situation in northern Sinai. He says that although things have become worse for them since the start of the "Arab Spring" in 2011, their troubles go back much further. Even today, Meyer told DW, older Bedouins remember — of all things — the years of the Israeli occupation of the Sinai Peninsula after the Six-Day War in 1967 as a "golden era."

"The Bedouins benefited not only from Israeli tourists but also from improvements in infrastructure, especially with regard to medical care, as well as from the job possibilities that the military administration offered them," he said. At the same time, according to Meyer, they earned money by cultivating drugs — an activity that was officially sanctioned — and smuggling them into the Egyptian heartland.

Political failure

Asiem El Difraoui sees the fact that the attacks are inspired by a militant form of Islam as being a result of the spread of Salafist ideas, which already took hold in the region decades ago. He said these ideas had taken an increasingly radical turn over the years, eventually turning into militant jihadism.

Günter Meyer feels that this radicalization has been fueled in part by the failure of attempts by the Bedouins to express their demands at a political level, with the leadership in Cairo turning a deaf ear to their needs. In addition, he said, the situation of the Bedouins has continually deteriorated since 1982, the year in which the Israelis withdrew from Sinai. According to him, the Bedouins had been particularly badly affected by the start of construction work on the as-Salam Canal Project.

The Bedouins lost some of their fertile tracts of land during the building of the irrigation canals, he says. "When the project area was redivided, these (tracts) went to settler families from the Nile Delta, while the original residents were allocated sandy territories in peripheral areas," Meyer said. When resistance by the Bedouins became more radical, the Egyptian authorities arrested a lot of women so that their husbands would turn themselves in, he added.

The roots of a disease

In 2014, barely a year after the ouster of President Mohammed Morsi, a member of the Muslim Brotherhood, some Bedouins joined the ranks of IS. The jihadists provided them with weapons from Libya. Since then, according to Meyer, violence has escalated even further. He said Egyptian armed forces had even bombed settlements and fired at them with tank shells in the course of the confrontation. "This reached its peak in the destruction of hundreds of houses to establish a buffer zone along the border to the Gaza Strip for security reasons," he said.

How can the terrorist violence in Sinai best be countered? According to Asiem El Difraoui, any purely military response is counterproductive. He said that Egypt has to return to dialogue.

"And the government of el-Sissi must go back to a more peaceable strategy. It is concerned only with the symptoms and not the roots of this disease," he said.

The alliance between some Bedouins and IS meant that, up to now, violence has been mostly directed against Egypt's Coptic Christians. But now, Sufis have also become a target for the terrorists, who see them as apostates disloyal to the radical interpretation of Sunni Islam propagated by the jihadis.

Günter Meyer suspects that the jihadis were also targeting non-Bedouin workers from the saltworks located near the site of the attack. This, he says, would indicate that the jihadis are waging not just an ideological conflict, but also a social one, conducted using the most brutal of means.