Haitian police said they have gunned down four suspects and arrested two in relation to the killing of President Jovenel Moïse, who was found assassinated early on Wednesday.
Police said other suspects were still at large, but promised to apprehend them one way or another.
“They will be killed or captured,” director of Haiti’s national police, Leon Charles, told the media.
Earlier, officials claimed the “presumed assassins” had been arrested by the police, however no details were provided.
Mr Charles, also told media that three police officers had been held hostage “in combat with assailants”, but were later freed.
“We blocked them en route as they left the scene of the crime. Since then, we have been battling with them,” said Mr Charles.
The killing of Mr Moise threatens more turbulence for a country already enduring gang violence, soaring inflation and protests against his increasingly authoritarian rule.
Interim prime minister Claude Joseph said the police and military were in control of security in Haiti, the poorest country in the Americas where a history of dictatorship and political upheaval have long undermined the consolidation of democratic rule.
The country’s interim prime minister Claude Joseph, speaking on a local radio station on Tuesday confirmed Moise had been killed, saying the attack was carried out by an “armed commando group” that included foreigners. He added the police and military were in control of security now.
Later on, in a televised national address, Mr Joseph declared a state of emergency across the country and called for calm. “The situation is under control,” he said.
He also called for an international investigation into the assassination and also added that the elections scheduled for later this year should be held.
“We need every single one to move the country forward,” Mr Joseph said.
The assassination was condemned by world leaders including US President Joe Biden and Britain’s Boris Johnson.
Haiti has asked the US government for assistance with the investigation, claiming the assassins could have escaped over the land border to the Dominican Republic or by sea.
The Dominican Republic said it was closing the border and reinforcing security in the area, describing the frontier as “completely calm”.
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