At least 60 people were killed and dozens more injured after a petrol tanker overturned and exploded in northern Haiti.
Late on Monday, the truck overturned in the coastal city of Cap-Haitien and exploded in a fireball, engulfing cars and homes in flames.
Hours later, a local hospital was overwhelmed with injured people as it pleaded for basic supplies and more medical staff.
Dozens of bodies were reported near the explosion site as some people used buckets to scoop up petrol from the truck and the street to take back to their homes, Dave Larose, a civil engineer who works in the region told AP.
It comes as Haiti struggles with a severe shortage of fuel and spiralling gas prices that recently forced hospitals to turn away patients and temporarily shut down gas stations, schools and businesses.
Such was the situation, the US and Canada urged its citizens to leave while they still could.
Officials believe the truck overturned and exploded after it tried to avoid hitting a motorcycle, Patrick Almonor, deputy mayor of Cap-Haitien said.
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He said he expects the number of deaths to keep rising because people who died in their homes have not yet been counted.
“It’s horrible what happened,” he said. “We lost so many lives.”
Mr Almonor said a local hospital is in dire need of more nurses, doctors and basic medical supplies to help those who had been injured.
Prime Minister Ariel Henry said he was devastated and announced that his administration was deploying field hospitals to the area to help those affected.
“Three days of national mourning will be decreed throughout the territory, in memory of the victims of this tragedy that the entire Haitian nation is grieving,” he tweeted.
Former prime minister Claude Joseph also mourned the victims, tweeting: “I share the pain and sorrow of all the people”.
Haiti is still trying to recover from the 7 July presidential assassination and a 7.2 magnitude earthquake that struck in mid-August, killing thousands of people.
Haiti, which has a population of more than 11 million people, has also seen a spike in gang-related kidnappings, including 17 missionaries with a US religious group in October.
Five were later released but 12 are still being held.