Cairo: Egyptian security forces are finding themselves increasingly bogged down in their four-year fight against a Daesh affiliate in the country’s northern Sinai Peninsula, despite billions of dollars in US counterterrorism aid. The struggle has cost the lives of hundreds of police and soldiers, including at least 20 in the past week.

On Monday, at least 18 policemen were killed when a suicide bomber detonated his explosives-laden car near their security convoy. The attack, near the heavily patrolled North Sinai provincial capital of Arish, was followed by clashes as other militants opened fire, a military spokesman said.

Daesh affiliate, known as Wilayat Sinai, asserted responsibility for the attack, claiming that the bomber “plunged himself into six of their vehicles and blasted his car.” The militants also destroyed several military vehicles, as well an ambulance and a firetruck.

Two days later, two more soldiers were killed in a gun battle after terrorists staged a failed assault on a security checkpoint in North Sinai, a military spokesman said. Again, Daesh claimed responsibility.

“We see this attack that is supposedly in a completely secure area, and it claims 18 lives,” said Mohammad Sabry, the author of a book on the Islamist insurgency in Sinai. “It’s a signal that things are still not really under control.”

Similar violence has unfolded every few weeks in recent months, underscoring the insurgency’s resilience, as well as its ability to mount complex, multi-layered attacks using the local terrain to its advantage.

Since July 2013, at least 1,000 security personnel have been killed in terrorist attacks across the restive Sinai Peninsula, according to data compiled by the non-profit Tahrir Institute for Middle East Policy. In 2017 so far, more than 200 security personnel have been killed there.

Wilayat Sinai alone has claimed more than 800 attacks across Egypt since its pledge of allegiance to Daesh in November 2014, said Nancy Okail, the Tahrir Institute’s executive director. Egyptian security forces, she added, have killed more than 2,500 suspected terrorists in counterterrorism operations in Sinai since 2013, although unofficial numbers reported by local media are significantly higher.

Although there have been fewer terrorist attacks this year than last, the number of fatalities has risen, Okail said. That suggests the militants are planning their operations more strategically and with the intent of creating maximum carnage, according to analysts.

With Daesh nearing defeat in Iraq and Syria, its affiliates are asserting themselves in other parts of the world, from North Africa to Afghanistan to the Philippines. The militants have penetrated the mountains of Tunisia and maintain a robust presence in Libya, despite the loss of their stronghold of Sirte last year.

In northern Sinai, Daesh-linked militants are leading the insurgency launched in the summer of 2013 after Egypt’s military removed the Islamist president, Mohammad Mursi, following popular protest against the government.

Daesh has also increasingly targeted Egypt’s Coptic Christians, who make up roughly 10 per cent of the country’s 94 million people. The tactic appears designed to sow further division, turning Egyptians against the government.

In 2015, Daesh affiliate in Sinai claimed responsibility for the downing of a Russian passenger plane shortly after it took off from the Red Sea resort town of Sharm Al Shaikh. That attack, which killed all 224 people on board, hit Egypt’s economy hard, as Russia halted civilian flights to the country and Britain and other nations stopped their airlines from flying to Sharm Al Shaikh, the source of a third of Egypt’s annual tourism revenue.

Monday’s attack came two months after Daesh terrorists killed at least 23 soldiers at a remote outpost near Rafah, the Egyptian town bordering the Gaza Strip, which was the deadliest attack on security forces in two years. Daesh snipers have also been killing policemen in recent weeks.

This week, Egyptian lawmakers issued a statement vowing to eradicate terrorism, and State Department spokeswoman Heather Nauert said, also in statement, that the United States “will continue to stand with Egypt as it confronts the threat from terrorism.”

Sabry and other analysts say they think the number of attacks and fatalities in the Sinai region could be much higher than the official tallies suggest. The Egyptian military has prevented journalists, local and foreign, from visiting northern Sinai, and any information released is at the government’s discretion.

Sabry, who keeps close contact with Sinai tribesmen and other sources, said he’s heard reports of recent attacks and clashes near Rafah. But nothing has been reported by the security forces or local media.

“It’s very difficult to understand exactly what’s happening,” Sabry said. “There has been an intensified blackout even worse than we normally endure in Sinai.”