The observers had been invited by the ZANU-PF's leader, President Emmerson Mnangagwa as part of his "guarantee" of a "free, fair and transparent election" and their verdict on the poll was mixed.
The United States Embassy in Harare is deeply concerned by events unfolding in Harare.
Zimbabwean soldiers appeared on streets of Harare on Wednesday, jumping out of several armoured vehicles to disperse opposition supporters after they clashed with police, footage broadcast by eNCA television showed.
The streets were calm on Thursday morning although many shops were shuttered in the city center. One independent candidate and a member from a party linked to Mugabe also won one seat each.
Elsewhere markets were open and queues formed outside banks - a common sight in Zimbabwe due to the country's chronic shortage of banknotes.
"Let me also warn such individuals and groups that no-one is above the law", home affairs minister Obert Mpofu said. And equally, we hold the party and its leadership responsible for any loss of life, injury or damage to property that arise from these acts of political violence which they have aided and abetted.
President Mnangagwa calls for calm amid Harare clashes
Waiting patiently for official results as per the constitution, ' Mnangagwa, 75, Mugabe's former right-hand man, said on Twitter . Observers from the Southern African Development Community and the African Union will also deliver reports on the polls.
Mnangagwa previously said the opposition was to blame for the violence, though some worldwide observers criticized the military for opening fire on unarmed civilians.
Both the main candidates in the fray, President Emmerson Mnangagwa and main opposition leader Nelson Chamisa, had earlier claimed they are set to win and observers had said the race was too close to call.
The country's electoral commission said that Zanu-PF won a two-thirds majority in the national parliament - prompting protests in the capital, Harare.
A government crackdown in Zimbabwe after Monday's elections has prompted worldwide calls for restraint. The electoral commission said it would start announcing results for the presidential race but then pushed it back at least 24 hours.
The 94-year-old former leader had been in power since independence from white minority rule in 1980 until he was forced to resign in November after the military and ruling party turned on him.
A credible and peaceful vote was meant to end Zimbabwe's worldwide isolation and draw in foreign investment to revive the shattered economy. It called for transparency in the release of results.
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But there is a broad consensus among USA intelligence agencies that Kangson is one of at least two secret enrichment plants. Across those decades, the fallen were "entitled to one certainty - that they will never be forgotten", Davidson said.
Under Mugabe, elections were often marred by fraud and deadly violence.
The MDC did not immediately respond to the parliamentary figures but its presidential contender Nelson Chamisa, 40, said the presidential results were being faked. We've more votes than ED [Emmerson Dambudzo].
On his official Twitter feed, Chamisa accused the ZEC of releasing the parliamentary results first to prepare Zimbabweans for a Mnangagwa victory.
"We are nowhere near where we expected to be, so I can quite see us going into the fifth day which is allowed by law - but we are working flat-out", commission chairwoman Priscilla Chigumba told journalists in the capital. Mr Mnangagwa was largely backed by traditional supporters of the Zanu-PF, including rural voters and the elderly who still believe the party has done a lot of good for the country of some 16 million people despite the excesses of Mr Mugabe's reign.
Mnangagwa, Mugabe's former right-hand man, was the clear election front-runner, benefitting from tacit military support and control of state resources.
But Chamisa, a lawyer and pastor, sought to tap into the youth and urban vote.
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Trump also touted a decrease in the United States trade deficit in the most recent quarter, calling it "one of the biggest wins". The second quarter figures included several one-time factors, that won't happen in the third quarter, according to economists.
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