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NAIROBI, Oct 29 (Reuters) - Somali pirates have hijacked a Japanese-owned chemical tanker in the latest such seizure in the Horn of Africa nation's notoriously lawless waters, a regional maritime official and a piracy watchdog said on Monday.
Andrew Mwangura, head of the East African Seafarers' Assistance Programme, said shipping sources in both Somalia and Japan had confirmed the vessel was seized eight nautical miles offshore on Sunday morning.
"We are trying to establish what demands they have, and how many people were on board," Mwangura told Reuters by telephone from the Kenyan port city of Mombasa.
"There are five well-organised pirate groups operating in Somali waters. We know the one which took this boat," he said.
An official from the International Maritime Bureau's Piracy Reporting Centre in Kuala Lumpur identified the vessel as the 12,000 deadweight-tonne Golden Nory.
"She has been taken into Somali waters, and we haven't heard anything from her since," the official said.
Quoting an IMB official, Japanese news agency Kyodo said the tanker had 23 non-Japanese crew on board, made up of its South Korean captain and South Korean, Filipino and Myanmar nationals.
A Comoros-registered cargo ship, the Al Marjan, also went missing off Somalia last week, making a total of five boats believed currently held there by pirates.
The other three boats are two Tanzanian fishing vessels, and a ship from Taiwan. The Japanese-owned boat taken at the weekend was carrying a Panamanian flag of convenience, Mwangura said.
The waters off Somalia, which has been in anarchy and without central government since 1991, are considered one of the world's most dangerous due to a proliferation of pirates.
Attackers generally use speedboats to surround and board vessels, often justifying their actions as measures against illegal fishing and toxic dumping.
Mwangura said boats with no business in Somalia should stay away, while those who have to go there -- such as contractors for the U.N. World Food Programme (WFP) delivering aid -- should only travel with escorts.
"Things are not good. We advise ships that are not going to Somalia to stay 200 nautical miles off the coast," he said.
Piracy off Somalia dropped briefly last year during the six month period in which most of the south was ruled by a hardline Islamist movement. But incidents have risen again since the sharia courts movement was toppled from Mogadishu at New Year. (Additional reporting by Luke Pachymuthu in Singapore)
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