CAIRO — Egypt's election committee says 98.1 percent of voters have approved a new, military-backed constitution in the first vote since a coup toppled the country's president.

Egypt's High Election Commission said Saturday that 38.6 percent of the country's more than 53 million eligible voters took part in the two-day poll. That's 20.5 million voters casting ballots.

This is the first vote since the military removed Egypt's first freely elected president, Mohammed Morsi, following massive protests in July. Officials view the vote as key in legitimizing the country's military-backed interim government and its plan for parliamentary and presidential elections.

But Morsi's supporters and his outlawed Muslim Brotherhood group boycotted the vote and have alleged the results were forged. The Brotherhood has vowed to keep up their near-daily protests.

Activists and monitoring groups have raised serious concerns over the atmosphere in which voting took place, with U.S.-based Democracy International saying that "arrests and detention of dissenting voices" took place ahead of the poll.

"A democratic transition should be characterized by an expansion of freedoms, but Egyptians have seen substantial restrictions on the exercise of their democratic rights," said Eric Bjornlund, Democracy International's president and head of the observation mission in Egypt.

Democracy International, which had some 80 observers in Egypt, said on voting days it noted that a heavy security deployment and the layout of some of the polling stations "could have jeopardized voters' ability to cast a ballot in secret." It also there was campaigning too close to the polling stations and lack of non-partisan domestic observers.

"There is no evidence that such problems substantially affected the outcome of this referendum, but they could affect the integrity or the credibility of more closely contested electoral processes in the future," the group said in a statement Friday.

In the lead up to the vote, police arrested those campaigning for a "no" vote on the referendum, leaving little room for arguing against the document.

On Friday, supporters of ousted Islamist President Mohammed Morsi took to the streets to denounce the draft charter. Morsi was deposed in a popularly backed military coup July 3 and the previous constitution was drafted under his government.

Some protests turned violent. Four people were killed in the ensuing clashes, Egypt's Health Ministry said Saturday. It said 15 people were injured nationwide.