A day after Haitian President Jovenel Moïse was killed by gunmen at his house outside Port-au-Prince, Haitian National Police (PNH) have apprehended several suspects and killed several more, according to various reports.

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On Thursday, PNH Chief Leon Charles announced police had captured the final suspects behind the attack and were now looking for the masterminds.

UN Special Representative of the Secretary-General for Haiti, Helen La Lime, while speaking at a press conference on Thursday said from the Haitian capital that four members of a group that attacked the presidential palace Wednesday have been killed by police and six others are in custody.

"A number of arrests have been made as the police are working very hard to arrest the commando that entered the compound and attacked the President and the First Lady," she said. 

"I'm also aware that a larger group of possible perpetrators have taken refuge in two buildings in the city and they are now surrounded by the police,” La Lime told journalists in New York via video conference.

She added that acting Prime Minister Claude Joseph, appointed by Moïse earlier this year, would remain the country's de facto leader for now. She urged the need for unity in the country and cautioned that things were too unstable for elections to be held at the moment. "Stakeholders need to set aside their differences and to chart a common way forward and overcome this difficult moment in a peaceful manner,"  she urged.

(With input from agencies)