Israeli policymakers are concerned that the Jewish state could become the object of a massive border attack by an Isis Egyptian affiliate, similar to the one which struck Egyptian security targets in the Sinai Peninsula this week, killing dozens of soldiers and policemen. Israeli media reports said the army had been placed on high alert along Israel’s border with Sinai, but an army spokesman said there had been no change in military readiness. “We have our eyes open and we are in full coordination with the Egyptian security forces,” the spokesman said.

The coordinated attacks on military checkpoints and security positions culminated in the firing of rocket propelled grenades at a police station in the town of Sheikh Zuweid. It was the largest onslaught since the group, Isis in the Sinai Province, began to fight the government four years ago. Israeli intelligence analyst Yossi Melman wrote in The Jerusalem Post that the attacks were an indication that the regime of Egyptian President Abdel-Fattah al-Sissi is “losing the war” against Islamic militants. On Thursday, Israel reopened border crossings with Egypt and Gaza it had closed after the attacks.

Israel has sought to help the Egyptian regime by allowing it to deploy more troops in Sinai than is allowed under the 1979 peace treaty between the two countries. Shaul Shay, former deputy head of Israel’s National Security Council, said: “We have to hope that the Egyptians will succeed in dealing with their problems before it spills over on us. This is a level of fighting we haven’t seen in Sinai and it bodes poorly for the Egyptians but also for Israel. We can very quickly get attacked in a similar format and for this we have to be prepared.”

Regarding Egyptian statements that the situation in Sinai was “under control”, Mr Shay, a colonel in the reserves, said: “Being under control is a limited thing. I assume that the Egyptian army has regained control for the moment. But is this the end of the story? Certainly not.”