With nearly three-quarters of results from the legislative vote tallied, President Emmerson Mnangagwa's Zimbabwe African National Union-Patriotic Front had won 110 of the 210 directly elected seats in the National Assembly, electoral commission officials said in the capital, Harare, on Wednesday.
Three people were killed after soldiers moved into Harare on Wednesday, firing live rounds and beating protesters.
Official results Wednesday showed that the ruling ZANU-PF party had easily won most seats in the parliamentary ballot strengthening President Emmerson Mnangagwa's prospects of holding onto power in the key presidential race.
The opposition alleges the elections have irregularities, saying voting results were not posted outside one-fifth of polling stations as required by law.
The opposition leader Nelson Chamisa's Movement for Democratic Change (MDC) had won 41 seats.
The Zimbabwe Electoral Commission announced that it will make public the presidential election results at 10 pm on Thursday evening. The ruling Zanu-PF party are on course to retain their Parliamentary majority. The government has said three people were killed.
The violence appeared to dash the hopes of Zimbabweans that the peaceful vote would lift them out of decades of economic and political stagnation under Mr Mugabe.
Britain called for "calm and restraint", urging "political leaders to take responsibility.at this critical moment", while Amnesty International said the "people must be guaranteed their right to protest".
Soldiers fired "randomly" and beat up bystanders who were not involved in the protests, said the Zimbabwe Human Rights NGO Forum.
Election observers from the European Union and the United States had also urged the electoral commission to start releasing results of the presidential election, saying further delays would undermine the credibility of the vote. Elections under Mugabe's 37-year rule were marked by violence against the opposition and alleged fraud.
Speaking in Harare this evening, President Mnangagwa said the hooliganism and violence came as a surprise, adding that the opposition party leadership is to blame.
Opposition protestors take to the streets of Harare, burning tyres and pulling down street signs.
It alleges that the governing Zanu-PF party has rigged Monday's elections.
In Harare, the contrast could not be starker with November, when hundreds of thousands filled the streets, hugging soldiers and celebrating their role in ousting 94-year-old Mugabe, the only leader Zimbabwe had known since independence in 1980.
The ruling party forced Mugabe to resign in November, when the military briefly seized control of the country, and replaced him with Mnangagwa, his former deputy and spy chief.
The clip and the AFP photo accompanying it are set to become symbolic of the violence and bloodshed that will mark the date August 1 2018 in Zimbabwean history forever.
"It is unfortunate that this election has descended into bloodshed, which could have been avoided if security forces had exercised restraint against protesters", said Colm Ó Cuanacháin, Amnesty International's Acting Secretary General.
Home Affairs Minister Obert Mpofu said those who violated election rules by prematurely declaring victory risked incurring the "wrath of the law".