A deadly gun battle between police and the men suspected of assassinating Haiti's President Jovenel Moïse has been raging in Port-au-Prince.

Police chief Léon Charles said four suspects had been killed and two detained but some remained at large and a manhunt was still under way.

"They will be killed or captured," the police chief said.

Moïse, 53, was fatally shot and his wife was injured when attackers stormed their home early on Wednesday.

Police chief Charles described dramatic scenes as officers confronted the alleged assassins.

"We blocked [the suspects] en route as they left the scene of the crime," he told a news conference. "Since then, we have been battling with them."

Officials say the suspects are well armed and had taken three police officers hostage, who have since been freed.

Charles urged residents to stay indoors for their own safety.

Brazen attack

The acting prime minister, Claude Joseph, has described Haiti as being "in shock" after the killing of Moïse.

Heavily armed assassins stormed the president's home in the hills above Port-au-Prince at around 01:00 local time (05:00 GMT).

Moïse was shot multiple times and died at the scene. The president's body had a total of 12 bullet wounds, Magistrate Carl Henry Destin told the Novelist newspaper.

He said the president's office and bedroom were ransacked and that he was found him lying on his back, covered in blood.

First Lady Martine Moïse was also injured in the attack and has been flown to Florida where she is said to be in a critical but stable condition.

The couple's three children, Jomarlie, Jovenel Jr and Joverlein, are reportedly in a "safe location", government officials said.

Destin said that Jomarlie had survived by hiding in her brother's room, while two domestic staff members had been tied up by the attackers.

Joseph described the gunmen as "mercenaries" and said that they were "foreigners who spoke English and Spanish". Haiti's official languages are Creole and French.

But Haiti's communications minister has since said that there were Haitians among the suspects.

Video released after the shooting purports to show heavily armed men dressed in black outside the residence shouting in English: "DEA [US Drug Enforcement Administration] operations, everybody stay down!"

Haiti's ambassador to the US, Bocchit Edmond, said that while the attackers had disguised themselves as US drugs agents, he believed there was "no way" they really were US agents.