Ethiopia will hold fresh ballots for around 20 out of 524 parliamentary seats, further delaying final results of the country's disputed May 15 polls, election board officials said on Friday, according to Reuters. The re-votes would be held on Aug. 21, election board spokesman Getahun Amogne said, adding the figure could rise pending the outcome of investigations into alleged vote-rigging. Claims of fraud in what was considered Ethiopia's most open election sparked protests and a military clampdown that left at least 36 people dead in Africa's top coffee-producer. Delays in the final results due to a probe launched on June 30 by international observers, lawyers and party officials have fuelled tensions among Ethiopia's 72 million people. In the May 15 polls, 524 seats in Ethiopia's 547-member parliament were contested. Partial results already released showed that Prime Minister Meles Zenawi's ruling party and its allies won 158 out of 307 seats announced so far.