Egypt remains deeply divided as anniversary of Mubarak's fall nears CAIRO -- As Egypt prepares to mark the third anniversary of the uprising that toppled longtime autocratic President Hosni Mubarak, planned remembrances of what seemed a euphoric moment of national unity are instead putting the country's angry divisions on display. Tensions are running high in advance of the weekend anniversary of the start of massive 2011 protests centered on Cairo's Tahrir Square. The upheaval in Egypt, the Arab world's most populous state, was a watershed of the revolts known collectively as the Arab Spring -- a regional movement whose democratic aspirations have gone largely unrealized. Egypt's military-backed interim government has sought to transform the anniversary, which coincides with a national holiday saluting the police, into a show of overt public support for army chief Gen. Abdel Fattah Sisi and the security forces that hold the country in a tight grip. But every day brings evidence of deep polarization. Many of the young people who took part in the Tahrir Square protests are bitterly disillusioned by what they see as a government bid to hijack the memory of the uprising's ideals. They showed that by staying away from the polls in last week's constitutional referendum. On Wednesday, a youth group that was a driving force behind the 2011 revolution reported that six of its members had been briefly detained by authorities for putting up posters calling for anniversary rallies of its own. They were held for nine hours before being released without being charged, the April 6 Democratic Front said. "Oppression of youth for merely handing out flyers is a clear invitation to rebel against injustice," the group warned. Also Wednesday, a court handed two-year prison sentences to three activists accused of vandalizing a state-erected memorial in Tahrir Square, dedicated to the "martyrs" of 2011 and subsequent turmoil. Activists viewed it as a show of hypocrisy on the part of authorities who had unleashed the security forces on mainly unarmed protesters, and attacked the monument with paint and hammers within hours of its dedication. The collision of hopes and realities is a recurring theme in Egyptian public life these days. Voters last week overwhelmingly approved a new constitution with provisions meant to strengthen personal freedoms, but the weeks leading up to the referendum coincided with a wave of prosecutions that government critics and human rights groups say appear politically motivated and ill-supported by evidence. Three well-known activists of the anti-Mubarak era recently received three-year prison sentences, which they are appealing, for violating a tough new anti-protest law. Twenty-five others, a mix of secular liberals and supporters of the Muslim Brotherhood, were charged this week with insulting the judiciary, a broad-brush accusation invoked in response to seemingly innocuous actions such as tweeting criticism of a court decision. Prior to last week's referendum, half a dozen people were jailed after putting up posters urging a "no" vote on the constitution. And three journalists from the news channel Al Jazeera English have been imprisoned since Dec. 29, accused of links with the Muslim Brotherhood and making false reports, among other offenses. A senior advisor to interim President Adly Mansour, Mostafa Hegazy, told journalists this week that the string of prosecutions was the fruit of an independent judiciary at work, not the result of any orchestrated government campaign against its perceived foes. "Some actions are criminalized by law," he said. At the moment, however, dissent of almost any stripe appears to be criminalized. Authorities have said tens of thousands of police would be mobilized to safeguard Saturday's commemorations. The Interior Ministry declared that any unlawful acts -- taken by most Egyptians to mean any anti-government gatherings -- would be met with force. The Muslim Brotherhood, meanwhile, made a rare acknowledgment of mistakes during the yearlong tenure of deposed President Mohamed Morsi, even while castigating the current government. The Islamist president was removed from office by the military in July following enormous protests against his rule. He is imprisoned and accused of a variety of capital crimes. Hundreds of his followers have been killed and thousands jailed. Public opinion has continued to run strongly against the Brotherhood amid the concerted government effort to crush the movement with arrests and use of deadly force. In its statement, issued late Tuesday, the group sought to remind Egyptians, in advance of the anniversary, of its own role in helping bring down Mubarak. "Continue our revolution!" it urged.