Sudan has begun voting in an election expected to be won by President Omar al-Bashir, the world's only sitting leader wanted on genocide charges.

As voting began Monday at 8 a.m. (0500 GMT, 1 a.m. EDT), police officers outnumbered voters and polling places stood empty in Sudan's capital, Khartoum. Opposition parties, citing a lack of freedom of speech and assembly in the African country, are boycotting the vote, which includes electing candidates for the country's legislative council.

Al-Bashir has ruled unchallenged for 25 years and presents himself as shield for stability. He survived the 2011 Arab Spring and his massive security apparatus has left the once-vibrant opposition a husk of its former self.

Nearly 13 million people are registered to vote. Results are expected on April 27.