The power struggle triggered by the assassination of Haitian president Jovenal Moise deepened over the weekend after the country’s most powerful gang leader called on his followers to take to the streets.

Jimmy Cherizier, who leads a federation of gangs called G9, said in a televised address on Saturday that gang members should rally in public to demand "light be shed on the president’s assassination."

Mr Cherizeir’s intervention came after Claude Joseph, the acting prime minister, called for help from US and UN troops as he tried to fend off at least three other rivals for power and avert a slide into street violence.

President Moise was gunned down at his Port-au-Prince residence on Wednesday in what Haitian authorities say was a contract killing by Columbian and American mercenaries.

Haitian authorities say 28 people – 26 Columbian and two American – were involved in the assassination. Of these eight are still at large and 17 were paraded in front of the cameras last week.

Jimmy Cherizier, alias Barbecue,calls for people to take to the streets to demand truth about the president's assassination

Credit: Raynald K. Petit Frere/Reuters

The group suspected of assassinating Haitian President Jovenel Moise told investigators they were there to arrest him, not kill him, the Miami Herald and a person familiar with the matter said on Sunday.

Mr Joseph has been broadly internationally recognised as the legitimate head of the interim government, but several figures inside the country have challenged his authority.

The nation’s nonfunctioning Senate on Friday voted to make its president, Joseph Lambert, the country’s acting president. The Senate has no legal authority because of a lapsed election schedule.

Earlier Ariel Henry, a 71-year old neurosurgeon who Moïse appointed as prime minister two days before he was killed, claimed he was the legitimate interim ruler and accused Mr Joseph of mounting a "coup" against him.

The acting government headed by Mr Joseph has dismissed both men as illegitimate opportunists.

Haiti is the poorest country in the western hemisphere, with nearly a quarter of the 11-million-strong population living below the poverty line.

It has long been divided between the bulk of the population and a small wealthy elite and for decades it was a kleptocracy ruled by the Duvaliers – first Papa Doc and then his son Baby Doc, who was ousted in a military coup in February 1986.

Moise’s killing and the ensuing political chaos came amid what the UN has called an "unprecedented" escalation of violence as rival gangs battle one another and the police for control of the capital.

Mr Cherizier, whose G9 is one of about 30 gangs police believe country roughly half of the capital, described Moise’s assassination as part of a national and international conspiracy against the country.

Wearing military fatigues and seated in front of a Haitian flag, he said: "We tell all bases to mobilize, to mobilize and take to the streets for light to be shed on the president’s assassination."

He also railed against businessmen of Syrian and Lebanese descent, who he described as “masters of the system” who dominate the country’s politics and economy.

"It’s time for Black people with kinky hair like us to own supermarkets, to have car dealerships and own banks," he said.

Mr Cherizier, known locally as “Barbecue”, is a former police officer accused by police and witnesses of helping to orchestrate the slaughter of up to 59 men, women and children in the nearby neighborhood of La Saline last year. He denies any involvement.

But he has tried to redefine himself as a political figure in recent weeks.

Last month, he gave a statement to local media outlets saying the G9 had become a revolutionary force to deliver Haiti from the opposition, the government and the Haitian bourgeoisie.

Wearing a face mask against the spread of the new coronavirus, a woman attends Mass in Port-au-Prince, Haiti

Credit: Matias Delacroix/AP

He himself is widely thought to be allied to Moise, and the words were interpreted as a warning to opposition figures blocking the president’s plan for constitutional and political reform.

The reform plans hinged on a referendum on September 26 along with presidential and legislative elections. Supporters of the late president, including his widow, say the assassination was intended to thwart those changes.

"They sent mercenaries to kill the president at his home with members of his family because of roads, water, electricity and the referendum as well as elections at the end of the year so that there is no transition in the country," Martine Moise wrote on Twitter on Friday.

Duberney Capador Giraldo, a former Colombian soldier killed during the operation to capture those allegedly implicated in the assassination of Haitian President Jovenel Mois

Credit: Jenny Capador Giraldo/Reuters

"The mercenaries who assassinated the president are currently behind bars but other mercenaries currently want to kill his dream, his vision, his ideology," she added.

She was badly wounded in the attack that killed her husband and is currently recovering in a Miami hospital.