Piracy in the South China Sea has hit a five-year high with tankers and large container ships most prone to attack, an international monitoring agency said Monday.

A spokeswoman for the information sharing centre of the Regional Cooperation Agreement on Combating Piracy and Armed Robbery against Ships in Asia (ReCAAP) told AFP there were at least 10 cases of sea attacks reported in 2009 so far.

This has surpassed the previous record of nine set during 2005, and more reported cases this year were still being verified.

The 10th case involved a Singapore-registered liquefied petroleum gas tanker boarded by six pirates on September 19, with the attacker assaulting the duty officer and robbing the ship's crew, ReCAAP said in an incident report.

Tankers and large container ships are targeted because they are "more vulnerable and slow-moving", ReCAAP's assistant director of research Lee Yin Mui was quoted as saying by Singapore's Straits Times.

ReCAAP aims to enhance inter-governmental cooperation against piracy and armed robbery in Asian waters among 15 nations. Its information centre is located in Singapore.

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