The recent elections held in Burundi which were wracked by violence and were boycotted by the opposition were neither free nor credible, UN observers said on Thursday, the day after clashes left six dead in the capital.
Parliamentary and local elections were held on Monday despite an appeal by UN Secretary-General Ban Ki-moon to postpone the polls after months of turmoil.
The UN electoral observer mission said in a report that the elections took place "in a tense political crisis, and a climate of widespread fear and intimidation in parts of the country."
"Episodes of violence and explosions preceded, and in some cases accompanied election day activities, mostly in Bujumbura," said the nine-page report.
The mission concluded "that the environment was not conducive for free, credible and inclusive elections."
The results of the parliamentary polls have yet to be released but Belgium has said it will not recognize the outcome and the United States ratcheted up international pressure Thursday, calling for presidential elections on July 15 to be delayed.
Clashes in the capital Bujumbura on Wednesday left six dead in the opposition stronghold of Citiboke district, which has seen weeks of protests against President Pierre Nkurunziza's rule.
Police said a grenade was thrown at a police patrol, injuring two officers and triggering gun battles in which one police officer died.
Five others, described as members of an armed group, were killed, but witnesses said they were brutally executed by police.
An AFP reporter at the scene saw the six bodies, three of whom had bullet wounds to the head.
The elections Monday set the stage for the presidential vote, but US State Department spokesman John Kirby urged Nkurunziza to delay the polls.
He urged the president "to place the welfare of Burundi's citizens above his own political ambitions and participate in dialogue with the opposition and civil society to identify a peaceful solution to this deepening crisis."
"This solution should include the delay of the July 15 presidential elections until conditions are in place for free, fair and peaceful elections," Kirby added in a statement.
Clampdown on opposition and media
The UN observers said ruling party candidates were able to campaign throughout the country but that opposition politicians were "much less visible."
The report described widespread media restrictions, with journalists targeted for assaults, detentions, attacks and expulsions.
International alarm has been growing over the crisis in Burundi, triggered by Nkurunziza's bid to run for a third consecutive five-year term.
Opponents say that is unconstitutional and violates a peace accord that ended 13 years of civil war in 2006.
At least 70 people have been killed and more than 140,000 have fled Burundi seeking refuge in neighboring countries.
The UN Security Council met to discuss the crisis and the way forward after hearing a report from envoy Abdoulaye Bathily.
Bathily cast doubt on the government's willingness to hold talks with the opposition to try to resolve the crisis, according to diplomats who were present at the closed-door meeting.
During a council meeting last week, Burundi's Ambassador Albert Shingiro described the opposition as "spoiled brats" who were making too many demands and insisted that the elections would go forward.
The council has been struggling for months to agree on a common stance on the Burundi crisis, with Russia insisting it is an internal matter and African countries reluctant to take a strong position.
New Zealand's Ambassador Gerard Jacobus van Bohemen, who holds this month's presidency of the Security Council, said the 15 members "expressed concern that the minimum conditions for free, fair, transparent and credible elections were not met."
East African leaders are due to address the Burundi crisis at their summit meeting on Monday.