CAIRO >> Neighbors are growing more suspicious of strangers asking questions or taking pictures. Blast walls and other barriers are crowding the streets. Commuters say they have grown accustomed to changing their routes to avoid traffic snarled by the inevitable security cordons after each new explosion.

Nearly two years of escalating bombings in and around the Egyptian capital are gradually changing the feel of the city, residents said Thursday, after militants calling themselves part of the Islamic State claimed responsibility for the latest blast. This time, it was a 2 a.m. explosion that damaged a security agency headquarters and wounded at least 29 people.

“The streets are empty, the places are empty, people have not left their houses” because of the bombing, said Dina Abou el-Souod, owner of a cafe and restaurant in downtown Cairo. “We feel the effects every day.”

Cairo was for decades a bastion of stability, especially compared with Arab capitals like Beirut or Baghdad. Then the Arab Spring uprising that removed President Hosni Mubarak in 2011 set off seemingly endless waves of street protests. Now the military ouster of President Mohammed Morsi of the Muslim Brotherhood two years ago has ushered in a new period of anti-government violence.

A long series of bombings has scared away investors, dashed hopes for a recovery of the tourist industry and reinforced a government crackdown on almost any dissent in the name of battling terrorism.

Human rights advocates say the government’s heavy-handed tactics are perpetuating a cycle of repression by driving some nonviolent opponents toward militancy. Even the current government’s most enthusiastic supporters say that they see no end in sight for the bombings.

Instead, residents say they focus on the limited nature of the violence so far.

In interviews Thursday, they emphasized that none of the attacks to date have caused large-scale casualties among Egyptian civilians. Most have targeted police or government buildings, judicial or security officials, empty businesses or utilities.

There are ominous exceptions. One bombing this spring, aimed at a temple in Luxor crowded with tourists, was foiled in the parking lot. Militants last week executed a Croatian employee of a French energy company who had been abducted on a highway near Cairo.

But many Egyptians in Cairo have begun to shrug off the pattern of low-grade bombings as just another inconvenience in a hectic city of 20 million people.

“There is a kind of normalization,” said Abou el-Souod, the cafe owner.

The bombing here Thursday emptied her tables on what is usually her busiest day, the start of the Egyptian weekend. “But it seems like the memory of the people is very short,” she said, “and tomorrow they will be back again.”

She said she had felt afraid of the Morsi government, fearing that Islamists might someday impose strict moral codes on other Egyptians. But in more tangible ways, she said, “we feel less secure these days.”

“What am I afraid of now? Going to jail,” she said, arguing that anxieties set off by bombings had empowered the police to make arbitrary or politicized arrests in the name of public security.

The police are acting as they did under Mubarak, like “they have the power to arrest anyone, and after events like last night — sitting in our cafe downtown we heard the bomb — the fear it creates feeds the ability of the police to keep doing what they are doing.”

“Many friends, many colleagues are in jail,” she said. “The new laws and the lack of clarity about them are scary.”

Wael Eskandar, a blogger and activist, was at home with his family in the Dokki neighborhood of Giza, across the Nile from Cairo, when the blast shook the glass windows of their apartment.

“My parents just said, ‘Yeah, I heard the bomb,’ and went back to what they were doing,” he said.

When the bombings began in 2013, “it felt like fear and ‘what are we going to do?’” he said. “Now I think people are feeling more frustrated and bored.”

Egyptians interested in politics worry about the government crackdown and think, “What are they going to do to us next because of this?” he said, echoing Abou el-Souod. “But on the personal level, for most people, it is just normalized in a way.”

Marwa Barakat, an urban studies researcher, said the bombings were changing “the built environment” of the city through an accretion of added barriers and road closings to protect embassies, government headquarters, police stations and other potential targets. And after each bombing, “the security surrounding the area makes the traffic crazy.”

But the biggest change, she said, was the rising suspicion among ordinary Egyptians, many fearful of attacks on their own neighborhood.

Earlier this week, neighbors in one area tried to stop and arrest her for taking pictures of a bridge, she said. “People were coming up saying, ‘This is forbidden’ and ‘This is not legal,’ as though filming a bridge were a big problem.”

Journalists, filmmakers, community organizers and others who ask questions on the street often face similar accusations.

“A lot of shallow suspicions are created by these bombings,” Barakat said, and the result has reduced the “public space” for politics and civil society that had opened up after the revolt that forced out Mubarak in 2011. “People don’t want to participate anymore,” she said, “and the bombings are one of the reasons.”

The wave of bombings began almost two years ago, after a series of mass shootings by security forces killed more than 1,000 demonstrators opposed to the military takeover. On Sept. 5, 2013, an early-morning bomb exploded on a crowded street in Cairo in a failed attempt on the interior minister and his motorcade. On Dec. 24, another bomb hit a police headquarters in the city of Mansoura, in the Nile Delta, killing 16 people. And on Jan. 24, 2014, a third hit a police headquarters in Cairo and badly damaged the Museum of Islamic Art.

All three are remembered as landmark events. But since then bombings have become almost routine. Amorphous new Islamist groups have targeted police stations, electric utilities and the storefronts of businesses believed to support the government. And the violence has spiked sharply this summer.

A bombing at the end of June killed the chief prosecutor, Hisham Barakat, on the streets of the capital. A few days later another went off outside the Italian Consulate. Then Croatian national Tomislav Salopek was abducted just outside the city.

Economists say the attacks have helped send the Egyptian stock market tumbling nearly 30 percent since a peak in February. They have also stirred anxieties among Western expatriates living and working in Egypt.

The killing of Salopek by the Islamic State “will change the perception of the security risk,” said Angus Blair, a financial analyst based in Egypt. He said companies “would increase significantly the personal security of foreign employees in Egypt” and might bar employees from bringing their families. “That is the way it is likely to go.”

Mohamed Ahmed, a supporter of the current government, said his home in the rundown neighborhood of Bab el-Khalq was blown open by a bomb in early 2014. He expected more bombs to come, he said. “The Egyptian people are not afraid.”

But Mayada Khaled, a 20-year old university student in the same area, said the violence was narrowing her life. “We used to be able to go out. Stay out late,” she said, but now her parents are worried. “We come back home by 9 p.m.”

Osama Mahmood, who lives near the Italian Consulate, said the explosion there last month opened a jagged crack in the wall of his kitchen. Then the bombing on Thursday — several neighborhoods away — shook his home again and widened the crack. This time his aging mother was so frightened, she fled outside and waited in the street for the rest of the night.

“This will continue,” he said resignedly, adding, “Under Hosni Mubarak, it was never like this.”

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