A nationwide referendum to open the way for Egypt's first multicandidate presidential elections passed overwhelmingly, officials announced Thursday, a day after the balloting, which was marred by police beatings of protesters.

In Washington, a White House spokesman denounced Wednesday's violence and said there was "no excuse" for beating demonstrators during the voting that President Hosni Mubarak (search) had called a crucial step toward democracy.

Mubarak, who has led Egypt for 24 years, now will face unprecedented opposition if he runs, as expected, for a fifth term in September. But critics say the constitutional change, which allows candidates to put their names on the ballot only with approval from Mubarak's party, is a sham.

Official results showed 83 percent of voters approved the constitutional changes. Turnout was 54 percent of registered voters — a figure the Interior Ministry said was higher than in any previous presidential referendum.

There was no independent, outside monitoring of the election results or turnout estimate.

A high turnout was important to the government, which has sought to portray opposition groups as a vocal minority out of touch with most Egyptians.

Mubarak's opponents, both Islamic and secular, have complained the constitutional changes won't lead to greater democracy as the government maintains. Instead, they say it lays down rules that ensure the ruling party's grip is strong.

Six opposition groups, including the popular Muslim Brotherhood (search), had urged voters to boycott the balloting.

White House press secretary Scott McClellan denounced the beating of protesters during the vote.

"We're very aware of the reports," McClellan said. "There is no excuse for attacks on peaceful demonstrators."

Asked specifically about women being beaten, McClellan said: "Anyone who attacks peaceful demonstrators should be arrested and tried. That's our view."

Plainclothes government agents beat protesters, then watched as supporters of Mubarak punched other demonstrators. Women protesters in particular seemed to be targeted for beatings by both plainclothes state security agents and pro-Mubarak supporters, according to several witnesses and Associated Press reporters at the scenes.

McClellan said, however, that the Bush administration believes Mubarak's initiative to put in place competitive presidential elections is an important step.

"We think that should be accompanied by international election monitors and a real campaign," McClellan said. "It must be free and fair in order for it to have the broadest possible support from the people of Egypt and the international community."

A pro-government newspaper on Thursday proclaimed in a banner headline: "With complete free will, Egyptians made their new 'history."'

Critics said otherwise.

The opposition Al-Wafd paper called the referendum "scandalous" and published front-page photographs of two of its reporters casting ballots in six different polling stations, criticizing a lack of proper judicial supervision. It also published photographs of what it said were polling station employees filling out ballots and inserting them in the box.

"The regime is incapable of fair political competition against the opposition — that's why they resort to these oppressive measures," says Mohammed Habib, deputy supreme guide of Muslim Brotherhood, Egypt's oldest and biggest Islamist group. "They are taking this referendum thing too personally. ... It's a matter of life or death for them."

Referendum critics say the draconian rules in the constitutional change mean any challengers won't be able to truly compete. Some opposition protesters held banners Wednesday reading, "Boycott the referendum. We want real freedom."

In one protest in Cairo on Wednesday witnessed by an AP reporter, more than a dozen members of the Kifaya opposition movement were beaten by supporters of Mubarak. The protesters tried to seek police protection but a high-ranking officer ordered his security men to withdraw.

Elsewhere, an AP reporter saw 150 Mubarak backers attack Kifaya (search) members, beating them with sticks. Some demonstrators took refuge in a building. One woman trying to leave the building was pounced upon by Mubarak loyalists who punched her and pummeled her with batons and tore her clothes, according to an AP reporter at the scene.

Despite such incidents, the vote went on peacefully in much of the country.