Over a quarter of the world's piracy occurred in Indonesia
A new report into marine piracy suggests there was a sharp rise in the number of attacks on ships last year.
The International Maritime Bureau says attacks are also becoming markedly more violent.
More than 20 sailors were killed by pirates in 2003 - twice as many as the previous year.
The board's piracy reporting centre, based in Malaysia, also says piracy is increasingly becoming an Asian problem, with Indonesia the most dangerous area.
According to the figures, 2003 saw the number of piratical attacks rise by 20% from the previous year.
South and East Asia recorded twice as many as the rest of the world put together.
The International Maritime Bureau, which produced the report, is pointing the finger at Indonesia.
More than a quarter of the world's piracy took place in its waters, and without action from the Indonesian Government, the figures will not drop, the board said.
In Bangladesh, the situation is also spinning out of control.
Incidents almost doubled last year over 2002.
Nigeria, Vietnam and India all have serious problems.
Around the world, more than 20 sailors are known to have been murdered by pirates last year.
Seventy are missing, presumed dead.
Other trends are also emerging: ships are now less likely to be hijacked for their cargo; attackers, possibly from militant groups, are seizing ships and ransoming their crew.
Another worry is that oil tankers have become a common target.
Not only is there concern about oil supplies being disrupted, but in the wake of the 11 September attacks, security experts fear a tanker could be used as a floating bomb to attack a city.