By BRIAN ROHAN, Associated Press

CAIRO (AP) — Egyptian authorities have intensified a crackdown on dissent ahead of next week's anniversary of the country's 2011 Arab Spring uprising, with police raiding apartments seeking signs of plans for organized protests and checking people's social media accounts.

Security forces questioned residents and searched more than 5,000 homes in central Cairo as a "precautionary measure" over the past ten days, aiming to ensure Egyptians do not take to the streets, as they have so many times in recent years, officials said Thursday.

Surveillance and intelligence was gathered over months, focusing on young, pro-democracy activists inside and outside the country, including foreigners, one of the senior security officials said. He added that some people have also been detained.

"We are very concerned and will not allow protests," he said, speaking, as his colleague did, on condition of anonymity because he was not authorized to brief reporters. "These movements are aimed at polarizing society and mobilizing the masses against the government," he added.

Security forces nationwide are bracing themselves for the anniversary of the 2011 revolt that toppled longtime autocrat Hosni Mubarak. Officials, including President Abdel-Fattah el-Sissi, have voiced concern over attempts to mark the anniversary with new protests and security forces have arrested a number of activists accused of planning demonstrations.

With thousands of Muslim Brotherhood members and even secular activists in jail, and many others having left country since el-Sissi led the army's 2013 overthrow of an elected but divisive Islamist president, massive demonstrations are unlikely in the capital's greater area, home to some 20 million inhabitants.

The security presence and incursions in Cairo have been greater than in previous years, when authorities also feared anniversary protests. The roundup of activists and the closure of several cultural venues in Cairo considered by authorities to be possible harbors for dissenting views also marked an escalation from previous pre-emptive clampdowns by security services.

Social media users have been particularly targeted this year, with several people affected by the roundups saying that police are asking to inspect Facebook and Twitter accounts to track acquaintances and gauge political affiliations.

Earlier this month, authorities arrested three people who administered over 20 Facebook pages, accusing them of using the networking website to incite against state institutions. Social media, particularly Facebook and Twitter, played a large part in organizing the 2011 uprising and other protests since then.

Ramy Raoof, a Cairo-based digital security and privacy expert said that those who air dissenting opinions publicly are the easiest to track and detain, although some administrators for pages organizing events were likely to have been victims of rudimentary hacking by police.

"The Ministry of Interior has been very active at targeting people to date," he said. "In order to get into the accounts and shut down pages they need to either trick someone into revealing a password, or use malware to get them to reveal personal data."

One Facebook event page that had been calling for mass demonstrations at Cairo's central Tahrir Square — the epicenter of the 2011 revolt and subsequent protest movements — was cancelled earlier this month after more than 50,000 users said they would attend, and a similar amount expressed interest in the event.

There was no way to determine how many of those who said they wanted to attend lived in Egypt or actually planned to march on the square, likely to be closely guarded by security forces. Facebook, contacted for this article, declined to comment.

State and the overwhelmingly pro-government private media have also been urging the public not to demonstrate on Jan. 25, which is also National Police Day, arguing that protests would bring only chaos. Weekly sermons at mosques, which are based on guidelines provided by the state, have also been preaching against demonstrating for weeks.

In central Cairo there has been a heightened police presence for days, with riot trucks and civilian cars carrying plainclothes officers prowling the streets day and night, often accompanying forces raiding apartments.

One resident, an online marketer, arrived home earlier this week to find a dozen plainclothes officers inside his building, coaxing the doorman to ask residents to cooperate by offering up their mobile devices for inspection.

"They wanted to see my mobile phone and my friend's tablet and they were checking others in the building," he said, speaking on condition of anonymity for fear of repercussions. "They went through the whole apartment of two of my neighbors, looking for anything like alcohol or personal items that could be an embarrassment."

The anniversary comes at a time when the economy, buttressed in the early days of el-Sissi's leadership by aid from Saudi Arabia and the Gulf, is growing slower than authorities had hoped, casting a cloud over el-Sissi's promises to set the country on track to prosperity. At the same time, a wave of suicide bombings and militant attacks has intensified since el-Sissi led the army's ouster of Islamist President Mohammed Morsi in 2013. Over the past year, most of these attacks were claimed by the Islamic State group.

Late Thursday, a bomb went off during a raid on a home in Cairo's twin city of Giza where militants were preparing explosives, killing six people including at least three policemen and one civilian, and wounding 13 people, police said in a statement.

Earlier in the day, an Egyptian affiliate of IS claimed responsibility for an attack on a checkpoint in the country's volatile Sinai Peninsula that killed five policemen. The Associated Press could not independently verify the claim, which was issued via a statement circulated by the group's sympathizers on social media, however the design and logo resembled previous IS claims.

The attack took place at midnight on Wednesday in the city of el-Arish and also wounded three policemen, the Interior Ministry said.

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Associated Press writer Nour Youssef contributed to this report.

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