The police chief for the north-west region, Jackson Hilaire, said at least seven people were killed and more than 100 injured in Port-de-Paix. Another four people died in and around the town of Gros-Morne further south, including a boy struck by a falling building, said the mayor, Jean Renel Tide.
Rescue workers reported the collapse of part of a hospital and an auditorium as the quake hit on a rainy evening.
The quake was one of the strongest to hit Haiti since a 7.0-magnitude quake struck near the capital, Port-au-Prince, in 2010, killing thousands of people in the impoverished Caribbean country.
In a post on Twitter, Haiti’s president, Jovenel Moïse, urged people to remain calm after the civil protection agency said the quake caused injuries and panic in northern towns.
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