Indonesia's political and economic situation is believed to be the main contributing factor

IMB report

The violence used in the attacks also soared, with at least 72 seafarers killed compared to three in 1999, according to the International Maritime Bureau (IMB).

It said 469 attacks or attempted raids on ships at sea, at anchor or in port were reported last year, compared to 300 in 1999 and only 107 in 1991.

On top of the 72 reported deaths, another 99 people were injured, up from 24 in 1999, and a further 26 seafarers are still missing.

Indonesian waters are the most dangerous

The IMB's annual piracy report noted an "alarming rise" in piracy and armed robbery in Indonesia, the Straits of Malacca, Bangladesh, India, Ecuador and the Red Sea.

Indonesian waters were the most at risk with 119 incidents in the region, which also saw the worst violence.

"Indonesia's political and economic situation is believed to be the main contributing factor to the alarming increase in attacks," the IMB said.

"So far there are no convincing signs that the number of attacks will drop in the near future unless Indonesia takes serious steps to try to address the piracy problems."

In one case last April, a group of around 20 people threw petrol bombs at a ship anchored in Indonesia after a raid in which one of the crew was stabbed in the stomach.

Patrols

The Malacca Straits, between Indonesia and Malaysia, was the second most dangerous region with 75 incidents in 2000, compared to only two in 1999.

Danger spots - attacks in 2000

Indonesia 119 Malacca Strait 75 Bangladesh 55 India 35 Ecuador 14

Source IMB

The Straits, one of the world's busiest shipping lanes, is used by 600 vessels a day.

The IMB said Malaysian police had increased patrols and formed a special taskforce to tackle the problem and hoped Indonesia would follow suit.

Bangladesh was the third most dangerous area, with 55 attacks, compared to 25 in 1999. But the report said there had been a recent drop in incidents.

In one raid in August a crew member on a vessel in Chittagong port was shot twice as he tried to fight off 12 armed pirates.

There were also 13 attempted raids in the southern part of the Red Sea, an area where there were no attacks in 1999.