Police say a gunman has shot and killed a man waiting to vote for president in Brazil's northeastern state of Rio Grande do Norte.

Police Sgt. Alfredo Carneiro told the G1 news portal that 20-year-old Robson Diego de Moura Soares was waiting in line to enter the polling station at a public school on Sunday when the gunman approached him and opened fire. The shooter then fled.

Carneiro said the two men apparently belonged to rival gangs in the city of Mossoro.

Dias Toffoli, president of the Superior Electoral Tribunal told reporters that the killing was not related to the election.