One man was shot dead and two others were wounded at the annual conference of Jamaica's ruling party minutes before Prime Minister Bruce Golding was due to speak on Sunday, police and witnesses said, Reuters reported.
Finance Minister Audley Shaw was addressing thousands of supporters at the Jamaica Labour Party conference in the capital and was preparing to hand the microphone to Golding when the shooting occurred behind the stage where members of the party hierarchy were sitting.
There was no immediate threat to Golding or Shaw, police said.
Police pronounced one man dead at the scene. A few minutes later two other people were shot outside the venue.
Party officials blamed the police for the shooting, though police have not taken responsibility.
"This is the first time that I was witnessing something like this since I started attending party conferences in 1968," said Golding, who continued with his speech after a pause.
"It means as a party we still have to do some house cleaning," he told the crowd.
Jamaica has the highest murder rate in the Western hemisphere with roughly 1,500 murders per year, but police said it was the first time in the country's recent history that someone has been killed at a party conference.
The center-right JLP took power in September 2007 in a general election defeating the People's National Party. They have set controlling crime, economic growth and education as their main priorities.
Jamaica has a population of 2.7 million people and is the largest island in the English-speaking Caribbean. Its economy depends on remittances from overseas, tourism, bauxite and aluminum mining and sugar exports.