As part of an ongoing war with Islamist militants now affiliated with ISIS, Egyptian authorities have been periodically shutting off phone and Internet service to portions of the country’s north Sinai region for over two years, sometimes severing entire towns from contact with the outside world.

The communications blackouts are one of the best illustrations of the intensity of Egypt’s ongoing military campaign in Sinai, in which hundreds of people have been killed over the past two and a half years in attacks by both insurgents and the Egyptian security forces.

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The cuts are an apparent attempt by the state to undermine the insurgents’ operations and prevent them from using wireless devices to detonate remote-controlled homemade bombs, which they have used to kill members of the security forces. But civilians living in Sinai say the cuts paralyze ordinary life and vital services like banks and ambulances. The scheme also intermittently plunges the people of north Sinai into an information black hole, and helps block the harsh reality of the conflict from those outside Sinai, including the media. The cuts themselves have gone virtually unreported in international media.

Human-rights advocates argue the blackouts are just one aspect of a broader policy of collective punishment of Sinai’s civilian population, including torture, house demolitions and enforced disappearances. Though the cuts on their own are far less destructive than military operations or other similar measures, Sinai residents and experts say the blackout strategy creates misery for the region’s civilians, rather than undermining the insurgents the Egyptian security forces are supposed to be fighting.

“Lately telecommunications were cut from morning until sunset, or sometimes until midnight,” says Moamar Sawarka, a human-rights advocate from the north Sinai town of Sheikh Zuweid. “Basically this kind of cutting is due to the campaigns and to cut the movements of jihadists and armed groups in Sinai. The Internet is cut and there’s no life.”

Even as civilians in the Sinai suffer from the blackouts, there is the mounting evidence that the insurgents have adapted to the communications cuts by adopting the use of two-way radios and possibly satellite phones, according to analysts and news reports. As a result, the telecom blackouts have effectively opened up another front in the struggle between the authorities and the militants: a battle for control over the airwaves.

“It gives you an idea of how the situation is still continually not that stabilized,” says Mokhtar Awad, an expert at the Center for American Progress in Washington, D.C., who tracks the Sinai conflict. “They’re very much having a difficult time keeping tabs on these people who after four years — three years and a half or so of operations or active presence — have really perfected the art of hiding in plain sight.”

In the course of its digital counterinsurgency, the security forces have attempted to interdict the smuggling of radios and other communications equipment into North Sinai, just as they work to stanch the flow of arms and insurgent personnel. In March, the military said it seized dozens of long-range wireless-data antennas and other equipment that it said smugglers attempted to import via an underground tunnel from Gaza. The equipment, which is commercially available in the U.S., uses a five-gigahertz signal, a band commonly used for wi-fi, and has a range of 100 km or more, meaning it could reach far into desert.

In February, officials said they seized an illicit shipment of 568 radio devices designed for use by police, according to a customs document released by the news organization Aswat Masriya. The equipment was concealed in a container labeled as holding children’s toys.

Several North Sinai residents said in interviews that the communications cuts began in earnest in 2013, around the same time the insurgency in Sinai metastasized following the military’s removal of Egypt’s Islamist President Mohamed Morsi. After years of neglect by the central state, Sinai has become an arena for militancy. Insurgent attacks accelerated in the power vacuum following the overthrow of autocrat Hosni Mubarak in the uprising of 2011. The tempo and scale of attacks increased dramatically following Morsi’s removal and the state crackdown on Islamist groups that followed.

The simmering insurgency took on an even more ominous character in November 2014 when the main militant group there, called Ansar Beit al-Maqdis, proclaimed its allegiance to ISIS, a few months after the self-proclaimed caliphate overran huge portions of Syria and Iraq. Since then, the gunmen who now call themselves the “Sinai Province” of the Islamic state have escalated their campaign against the government, carrying out frequent attacks on the security forces in Sinai, Cairo, and elsewhere in the country.

Last summer, militants bombed a security headquarters in Cairo, injuring 29 people, and assassinated Egypt’s chief prosecutor in a daylight car bombing in Cairo (that killing was blamed on a separate group of militants led by a former military officer). The Sinai Province also claimed responsibility for the beheading of a Croatian man and firing a rocket at an Egyptian naval vessel in the Mediterranean. On July 1 jihadists also launched a coordinated assault on military positions, triggering fighting that left at least 17 soldiers and more than 100 militants dead, according to the armed forces.

The group also claimed to have brought down a Russian airliner that crashed in Sinai on Oct. 31, killing 224 people. The Egyptian government insists it has found no evidence that the crash was the result of an attack, placing Cairo at odds with the conclusion of the Russian security agencies, who said the plane was brought down by explosives. The crash marked another apparent escalation by the Sinai group, signaling an aspiration to inflict massive civilian casualties.

In September and October, Egypt’s military launched an offensive in North Sinai, claiming to kill more than 400 militants, although those figures are nearly impossible to verify because outside journalists are essentially banned by the authorities from entering the theater of conflict. More recently, the rate of insurgent attacks slowed but did not cease. In late November the militants attacked a North Sinai hotel, killing seven people including two judges overseeing a parliamentary election.

As the fighting intensified, the communications cuts became more frequent. The blackouts also vary in duration and geographical scope. In towns near the border with Israel and Gaza, such as Sheikh Zuweid and Rafah, the ongoing cuts take place nearly every day, eliminating cell-phone coverage, landline phones and Internet, from morning until night, according to residents and experts. In the regional hub, el-Arish, residents say the cuts are now less frequent, but still affected the city on multiple occasions.

Brigadier General Mohamed Samir, a spokesperson for the Egyptian military, said he could not comment on the blackouts because “these communications cuts are not carried out by the armed forces.” He referred questions to a spokesman for the Prime Minister’s office, who also declined to comment.

But the security forces’ apparent justification for the cuts has been disclosed in other ways. An unnamed security source quoted by the news site Masr al-Arabia said that a 12-hour outage on Nov. 30 was imposed in order to prevent the detonation of improvised bombs and disrupt insurgent groups’ communications.

Ramy Raoof, a technology consultant based in Cairo, says the cuts are likely imposed directly by the state and do not necessarily require the cooperation of the local telecom companies, because of the broad powers granted to the military and security forces in Sinai. He says, “In Sinai they don’t need to coordinate. They own the stuff so they just go and do it.”

The Ministry of the Interior as well as state telecom provider TE Data and Vodafone Egypt also did not respond to requests for comment.

In the towns and villages between el-Arish and the border, the cuts have frustrated daily life, disrupting everything from banks to government offices. One man from the border zone who speaks on condition of anonymity for fear of reprisal says, “When they cut it, they cut everything.”

Residents and experts say the cuts could backfire by preventing the local populace from aiding the security forces by sending information to the military — especially since the insurgents themselves seem to be able to bypass the blackouts. By hampering medical and emergency services, the blackouts could even endanger lives, they argue.

“They’re doing it indiscriminately. They could disable phone calls except ambulances, for example,” says Raoof. And still, he says, “It doesn’t prevent the bad guys from doing bad things.”

Sinai residents have also adapted to the cuts by relying on cellular networks beamed across the border from Israel and Gaza. According to Zack Gold, a fellow at the Atlantic Council, this mobile spillover has even become a point of contention between Egypt and Israel. “It’s something that the Egyptians complain about to the Israelis, about the mobile spectrum, or the cellular spectrum crossing into their territory,” he says.

Monitoring groups say the cuts are part of a larger pattern of abuses by Egyptian authorities the Sinai. Recently, the state displaced at least 3,200 families through a policy of demolishing homes near Egypt’s border with the Gaza Strip, according to an exhaustive 84-page report published by Human Rights Watch (HRW) in September. The government says the demolitions are a necessary step in order to end militants’ smuggling of weapons and people through underground tunnels between Sinai and Gaza. HRW disputes that argument, saying the weapons now in the hands of Sinai insurgents are more likely to have been smuggled from Libya.

Some Sinai residents also connect the disruption of communications to what they say is a long-standing policy of state neglect of the territory. Sinai’s local Bedouin community has long been barred from joining the military and most of the security forces, a fact that cuts that community off from pensions and opportunities in the Egyptian economy that is largely dominated by the military. The Bedouin also say they have been sidelined from Egypt’s formal economy, with the development of resorts and industries like cement benefiting “mainland” Egyptians from the Nile Valley. Sinai residents also complain of electricity and water cuts, as well as a curfew that confines residents in their homes as early as four or five in the afternoon.

The periodic severing of contact with people in North Sinai also creates a further obstacle for journalists, analysts, human-rights advocates, and anyone else seeking to establish the facts of the situation in Sinai. With foreign journalists barred from the area by the government, phones and Internet are some of the only lifelines to the outside. Even then, civilians fear both the long arm of the military and the violence of the insurgents, and are hesitant to speak openly. As a result, the specifics of battles and bombings are hard to determine. The civilian toll of this ongoing war is hard to know, and harder to confirm.

Amid the dearth of clear information, only the most persistent voices break through. And often, those voices are the most strident. That includes ISIS supporters, who continue to publish a daily drip of propaganda in spite of the cuts, either circumventing the blackouts or relying on external media support, possibly from the central ISIS organization. “When you do limit the outflow of information, the few people who are able to get through are obviously the most dedicated and would at least have an agenda,” says Awad. The jihadists’ message often filters through, even as the voices of ordinary people are increasingly absent.

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