PORT-AU-PRINCE, Haiti — A bus driver fleeing the scene of an accident drove into crowds of people in northern Haiti early on Sunday, killing at least 38 and injuring about a dozen more, the authorities said.

The bus, which was traveling from Cap Haitien to Port-au-Prince, the capital, initially hit two people at a bus stop outside Gonaives in the northern part of the country, according to Joseph Faustin, the head of civil protection for the Artibonite department. One of the two pedestrians was killed, he said.

The bus driver then tried to drive away, but when he reached Mapou, about three miles away, he crashed the bus into three rara parades, Mr. Faustin said.

The parades, which usually take place around Easter, involve groups of musicians playing traditional instruments in the street, often joined by crowds of passers-by.