Piracy on the international high seas surged 37 percent to an all-time high of 234 attacks from January to June this year, with 16 seafarers killed, the International Maritime Bureau (IMB) said.

Ships were boarded in 165 instances and nine ships were hijacked, the Kuala Lumpur-based IMB Piracy Reporting Centre said in a statement yesterday.

The number of deaths of seafarers around the world was sharply up, with 16 killed and 52 injured compared to six killed and 21 injured in the same period last year.

Indonesian waters were the most dangerous, "accounting for over one quarter of the world total with 64 incidents".