Evo Morales
Evo MoralesReuters

Bolivian President Evo Morales announced his resignation on Sunday following weeks of unrest over a disputed election that he had claimed to win.

His announcement came hours after the Organization of American States called for a new a presidential election in Bolivia, citing irregularities in the October 20 vote.

A preliminary report by the organization found a "heap of observed irregularities" in the presidential election.

The attorney general's office in Bolivia then said it would investigate the judges on the electoral tribunal.

Earlier on Sunday, Bolivia's military chief, Gen. Williams Kaliman, called on Morales to resign so that stability can be restored.

Speaking on national television, Kaliman also appealed to Bolivians to desist from violence.