An Egyptian party led by a prominent Islamist says it has decided to boycott the referendum on the country’s draft constitution, slated to be held today and tomorrow, in protest over the arrest of several of its members.

The two-day referendum is the first opportunity Egyptians have had to offer an electoral opinion on the country’s military-backed government since the army ousted Islamist President Mohammed Morsi last July. Opponents of the military takeover are hoping either the turnout will be low or that a majority will vote against the new charter, delivering a blow to the army’s morale and depriving the military of claiming that the vote amounts to a popular sanctioning of last summer’s coup.

Several activists from the Strong Egypt party—founded by the Islamist former presidential candidate Abdel-Moneim Abolfotoh and which includes liberals and moderates drawn from across the country’s political spectrum—were arrested in three separate incidents after campaigning against the army-endorsed constitution. The party includes liberals and moderates drawn from across the country’s political spectrum.

Party Secretary-General Ahmed Salem said the decision to boycott is in response to “very negative indications” in recent days, including the arrest of at least seven party members for hanging posters against the constitution.

In a statement Human Rights Watch said, “Egyptian citizens should be free to vote for or against the new constitution, not fear arrest for simply campaigning for a ‘no’ vote.”

Over the weekend hundreds of pro-Morsi students clashed with security forces at three universities in Cairo—the latest violent confrontations between protesters and security forces in the run-up to a referendum that is widely seen as clearing the way for General Abdul-Fattah el-Sisi, Egypt’s main decision maker, to formally declare a run for the presidency.

The clashes began on the campuses of Cairo University in Giza and Al-Azhar University in Cairo, along with Ain Shams University, then moved into neighboring streets with the students blocking main roads, hurling Molotov cocktails and chanting slogans against the generals and calling for the reinstatement of the ousted Islamist Morsi. Several students were injured in the clashes, in which police fired tear gas.

Speaking on Sunday at a military seminar, army chief General el-Sisi called on Egyptians not “to embarrass me in front of the world” by voting against the draft constitution or boycotting the referendum. He avoided linking his possible run for the presidency with the referendum’s outcome but U.S. officials briefing American lawmakers last week said they expected el-Sisi would run and face only token opponents.

“If I run, then it must be at the request of the people and with a mandate from my army,” General el-Sisi said at the seminar, adding, “I can’t turn my back on Egypt.”

How many Egyptians will turn out for the referendum remains unclear and the army is nervous about the outcome, judging by the flood of endorsements on both the country’s state-run and privately-held television and radio stations for a constitution that will entrench military power in the country’s politics. The referendum process has earned criticism from foreign watchdogs and NGOs with the Carnegie Endowment for International Peace, a Washington DC-based think tank, describing it as “flawed and undemocratic.”

Several Western democracy and governance groups that normally observe controversial elections have held back from sending teams to monitor this one, either because they fear their staff could be endangered or that the very act of monitoring will been as them legitimizing the referendum.

If passed, the new constitution that was drawn up by a 50-stong drafting committee, which included only two Islamists, will replace a constitution that was voted on just eight months before Morsi’s ouster. That constitution, which was heavily influenced by Islamists and drew only a 33 percent turnout for a referendum in December 2012, was criticized by liberals and secular activists for failing to protect civil liberties and for its provisions drawn from religious Sharia law.

The army and supporters of Morsi’s ouster are promoting the new draft constitution as a big improvement on its predecessor, especially when it comes to guaranteeing the rights of Christians and women. But it has been attacked by both liberals and Islamists for entrenching the power of the army with provisions allowing civilians to be tried in military courts and placing the defense budget beyond civilian oversight. It gives also the military total control over the appointment of a defense minister.

Political parties have been divided over the referendum and new constitution. The Salafist Nour Party as well as some liberal groups, including the Tamarod (Revolt) movement that was key in the popular rebellion against President Hosni Mubarak in 2011, has called for a “yes” vote. But the Muslim Brotherhood, which is now banned as a terrorist organization, and secular groups such as the April 6 Youth Movement that opposed both Mubarak and Morsi are against the vote.

Egypt’s Interim President Adly Mansour has urged the country’s 52 million voters to participate, arguing the constitution “paves the way to serious and steady steps toward democracy.”

But Egyptian author Ahdaf Soueif fears the referendum is merely hardening political divisions in the country—both over Morsi and his ouster and about the steps forward. “This situation can only be held together by oppression,” she said.

So far the signs are that the turnout will disappoint the army. Egyptians living abroad have voted in half the numbers compared to the referendum on Morsi’s constitution, although electoral officials say this is due to the scrapping of a postal vote, forcing Egyptian expats to go to embassies to vote. Approximately 103,000 expatriates voted while 244,000 ballots were cast in the previous referendum.