The bus, which was traveling from Cap Haitien to the capital Port-au-Prince, initially hit two people in a town outside Gonaives in the north of the country, killing one, said Joseph Faustin, civil protection head in the Artibonite department.
The bus driver then fled and crashed into three "rara" parades in Mapou, about 5km away.
Rara parades, which usually take place around Easter, are groupings of musicians playing traditional instruments who are often joined by passers-by.
