The National Electoral Board of Ethiopia (NEBE) said Wednesday complaints on 75 constituencies, lodged by contesting parties, have been dropped.
Mekonnen Wondimu, senior official with NEBE, told journalists that the complaints were rejected since they were not substantiated with convincing evidences.
He said complaints on 17 constituencies filed by the ruling Ethiopian People's Revolutionary Democratic Front (EPRDF) were rejected.
Complaints lodged by the opposition Coalition for Unity and Democracy (CUD) on 34 constituencies, were dropped after hearing the complaints for the second time.
And complaints filed by another opposition, the United Ethiopian Democratic Forces (UEDF) on 19 constituencies, also failed to merit investigation.
NEBE is responsible for the administration, conduct and supervision of all elections in Ethiopia's federal and state constituencies.
Earlier Tuesday, CUD and UEDF, the country's two major opposition parties, said in a joint statement that NEBE had rigged from the investigations into irregularities in 139 of the 524 seats contested in the May 15 parliamentary polls.
NEBE started the investigations after police shot dead at least 36 people during a protest against alleged electoral fraud.
On July 8, partial official results, released by NEBE, showed the ruling party and its smaller political allies won 158 seats to 148 seats for the opposition coalitions in the 547-seat lower house of parliament.
Results for the remaining seats will be released this coming Friday after the electoral body finishes investigations.
Ethiopians went to poll on May 15 in the country's two separate elections to elect representatives to the House of People's Representatives and eight regional councils.