Two men were shot dead as they walked to a match at a stadium that will be used for the 2014 World Cup in Brazil.
Police sources, reported by Globo, said the men had been near the Arena Castelao stadium in Fortaleza when the shooting happened on Sunday.
The reports said the victims, who were fans of Ceara, were shot from a passing vehicle that was allegedly carrying two Fortaleza supporters.
They said the shooting happened after fighting broke out when Ceara fans threw stones at their rivals. A man has been arrested in connection with the deaths.
Ceara beat Fortaleza 1-0 in a Cearense state championship match, with the game being considered a first rehearsal for the summer Confederations Cup.
Officials said the shooting had not been directly related to the match itself, adding that they considered general preparations for the Confederations Cup to have been a success.