An unidentified gunman has shot dead the director of a bus drivers' union in the Brazilian city of Sao Paulo.
Sao Paulo's public transport system faces a power struggle
Police said Paulo Goncalves was outside his union's headquarters when two men drove up on a motorcycle.
Witnesses saw one man get off and fire five shots at Mr Goncalves before the pair drove off again.
It was the 10th killing of a transport workers' union leader in the city in three years, said police.
It is thought the killing on Sunday was linked to a power struggle between rival bus companies in Sao Paulo, which are facing efforts by the city authorities to unify the transport system and reduce the number of bus service operators.
Police believe it was a contract killing and are due to issue an artist's impression of the suspect.