A US delegation and other dignitaries have hurried to vehicles as reports emerged of shots fired and crowd control gas used on protesters outside the funeral of late Haitian president Jovenel Moise.
Reuters witnesses smelled the gas and heard detonations they believed to be shots.
There were no immediate reports of injuries among protesters or authorities and no indications any guests at the funeral were in danger.
A brass band and church choir opened Moise's ceremony minutes earlier as his wife looked on, two weeks after a still-unexplained assassination at their home by foreign mercenaries.
The service was punctuated by angry shouts of protest by supporters accusing authorities of responsibility for Moise's death, their words sometimes drowned out by loud swells of taped sombre church music.
US President Joe Biden's ambassador to the United Nations, Linda Thomas-Greenfield, led the US delegation at Cap-Haitien to pay respects to Moise, joining mourners who have taken part in a series of commemorations in Haiti this week.
Haitian officials arriving at the event met with protesters' verbal anger, with one man calling police chief Leon Charles "a criminal".
"Why do you have all this security, where were the police on the day of the president's assassination?" one protester said.
Inside the auditorium where the Roman Catholic funeral was held, four pallbearers in military attire solemnly stood by the closed wooden casket.
It was draped with a Haitian flag and set on a dais garlanded with white flowers.
Protests by supporters of Moise have convulsed the northern city of Cap-Haitien, the slain leader's hometown, for three days.
Amidst the protests, workers paved a brick road to Moise's mausoleum on a dusty plot enclosed by high walls.
Set on land held by Moise's family and where he lived as a boy, the partly built tomb stands in the shade of fruit trees just a few steps from a mausoleum for Moise's father, who died last year.
A former banana exporter, Moise failed to quell gang violence that surged under his watch and he faced waves of street protests over corruption allegations and his management of the economy.
The demonstrators in Cap-Haitien were venting anger over the many questions that remain unanswered about the assassination, including who planned it and why.
Banners celebrating Moise festooned buildings along the narrow streets of Cap-Haitien's old town, with proclamations in Creole including, "They killed the body but the dream will never die," and "Jovenel Moise - defender of the poor".
Jovenel's widow, Martine Moise, her face nearly hidden under a wide-brimmed black hat and her right arm in a sling after being injured in the attack, paused at the coffin.
"Cry for justice. We don't want revenge, we want justice," she said.
Australian Associated Press