The economic turmoil means shipping in the strait between Indonesia, Malaysia and Singapore - one of the world's busiest - will be at extra risk, navy spokesman Sagom Tamboen was quoted as saying by news website Detikcom.

'We predict that with the global crisis, there will be more pirates and illegal activities taking place in the Malacca Strait. Coordinated patrols with Malaysia and Thailand will be maximised,' Mr Tamboen said.

He was not quoted as saying why he thought the global economic slowdown would increase piracy.

The maritime corridor, which handles 30 per cent of all sea transport globally, has traditionally been a piracy hot spot, but joint patrols have significantly cut attacks in recent years.

In the year to September there were only two pirate attacks in the straits, according to the Malaysia-based International Maritime Bureau (IMB), compared to 38 in 2004 and a peak of 75 in 2000. -- AFP