Armed gunmen belonging to the Gran Grif gang passed through the town of Pont-Sonde with automatic rifles, shooting at residents on Thursday, according to the United Nations' Human Rights Office.

"We are horrified by Thursday's gang attacks in the town of Pont-Sonde in Haiti's Artibonite region," a spokesperson said.

At least 16 people were also seriously injured in the attack in the early hours of Thursday, according to the UN.

Gang members were said to have set fire to at least 45 homes and 34 vehicles, forcing residents to flee.

Gang violence in Haiti is rampant and has brought parts of the country to a stand still.

Sky News's Stuart Ramsay previously interviewed a man known as Barbecue, one of the country's most powerful criminals.

Bodies lay strewn on the streets of Pont-Sonde, in the Artibonite region, many of them shot in the head, a spokeswoman for the Commission for Dialogue, Reconciliation and Awareness to Save the Artibonite, told Magik 9 radio station.

Among the victims were a young mother, her newborn baby, and a midwife, it was added.

In total, it was said that ten women and three children were among the dead.

Video of the attack showed hundreds running for their lives.

The motive for one of the biggest massacres in the country's central region in recent years remains unclear.

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Attacks of that kind have taken place in the capital Port-au-Prince, which is 80% controlled by gangs, and they are typically linked to turf wars.

While rival gang members generally target areas controlled by one another, Pont-Sonde is considered a part of Gran Grif's own territory.

The Haitian government deployed an elite police unit based in the country's capital to Pont-Sonde following the attack and sent medical supplies to the area's lone hospital, overwhelmed by the dozens of people injured.

"This heinous crime, perpetrated against defenceless women, men, and children, is not only an attack on these victims, but on the entire Haitian nation," Prime Minister Garry Conille said in a statement Friday.

In an audio message shared on Thursday, Gran Grif leader Luckson Elan, who was sanctioned by the UN last month, blamed the state and victims for the attacks, accusing residents of remaining passive as his soldiers were killed by police or vigilante groups.

"It's Pont-Sonde residents who are at fault. What happened in Pont-Sonde is the fault of the state," he claimed without evidence.

Gang violence across Artibonite, which produces much of Haiti's food, has increased in recent years.