More than 170 inmates have escaped from a Haitian prison in Arcahaie, 45km (30 miles) north of the capital Port-au-Prince.
The inmates stole five rifles; a guard and an inmate were killed in an exchange of fire.
The authorities have begun a manhunt for the fugitives with the help of UN peacekeepers stationed in the country.
The Haitian government tweeted that it condemned what it described as a prison mutiny.
“One guard was killed during the incident,” Justice Minister Camille Edouard Junior told Reuters news agency.
“Three prisoner were wounded, including one who died as a consequence of his wounds.”
Eleven escapees have so far been detained, and checkpoints have been set up on roads near the prison.
However, inmates at Arcahaie do not wear prison uniforms, making it easier for them to blend in with the general population.
Haitian prisons are notoriously overcrowded and inmates spend years in pre-trial detention.