Officials in Equatorial Guinea say voters have given virtually unanimous support to proposed constitutional reforms.
The government says about 99 percent of voters backed new presidential term limits and the creation of a vice presidency in Sunday's referendum.
The results Monday covered a little more than half of the vote. Final results are expected Wednesday, but opposition politicians rejected the initial count as a sham.
Critics say the new constitution will increase President Teodoro Obiang Nguema's authority and allow him to handpick his successor. The opposition says Mr. Obiang would likely choose his son to fill the vice presidential slot.
Mr. Obiang's government says the reforms will provide better oversight of the executive branch, and improve both human rights and the judicial system.
The new constitution also removes an existing maximum age limit for the president, which would allow the 69-year-old Obiang to continue running for president after he turns 75.
Mr. Obiang has been in power since 1979. The anti-corruption group Transparency International ranks Equatorial Guinea among the world's 12 most corrupt countries.
The U.S. Department of Justice recently accused President Obiang's son of stealing, extorting, and embezzling more than $100 million and laundering most of the money in the United States.
Human Rights Watch says Teodoro Nguema Obiang Mangue is also under investigation for corruption and money laundering in France and Spain.