KUALA LUMPUR, Malaysia — Add another problem to the rising tensions in the South China Sea this year: a mysterious spate of tanker hijackings since late April, as armed bands of men have boarded and commandeered the ships, siphoned their cargos of diesel and gasoline onto barges or other tankers, and fled into the night.
Complicating matters is the fact that two of the hijackings took place near the heart of Malaysia’s offshore oil and gas production, in waters where China is making an increasingly forceful claim to sovereignty.
Interpol, intelligence agencies and military forces in the region are investigating the eight attacks — the most recent of which was last Friday — and are trying to figure out how to stop further ones, said Noel Choong, the head of the Asia office here of the International Maritime Bureau’s Piracy Reporting Center.
One goal of the investigation is to determine whether the diesel fuel and gasoline are being sold for profit by criminals or are being used to finance political activities, possibly even terrorism.
In contrast to the military assault rifles sometimes carried by pirates off Somalia and Nigeria, the pirates in the South China Sea have tended to be armed with handguns or even machetes. No one is known to have been killed in any of the hijackings, but three tanker crew members were abducted in one of the incidents and have not been seen since.
The hijackings raise geopolitical issues. Seven have taken place close to Malaysia and one close to the Anambas Islands of Indonesia. But two of the hijackings close to Malaysia occurred in waters near James Shoal, a disputed, submerged reef near the north coast of Malaysian Borneo.
But China has been increasingly assertive over the past several years in claiming that James Shoal lies inside its so-called nine-dash line, a huge expanse of the South China Sea that Beijing has been claiming with increasing boldness, particularly this year. A small flotilla of Chinese naval vessels went to James Shoal in January, and Chinese officers held an oath-swearing ceremony there to pledge that they would defend China’s sovereignty.
The hijackings also come at a time of considerable nervousness about jihadist recruiting efforts in Malaysia, which is heavily Sunni Muslim. The Malaysian authorities have detained more than a dozen people in the past month, reportedly including a Malaysian naval officer, in an investigation into recruiting and other support activities on behalf of the Islamic State of Iraq and the Levant, the militant group that has seized control of a large part of northwestern Iraq.
In a typical year, one tanker, or even none, is hijacked in the South China Sea or the adjacent Strait of Malacca. Freighters and pleasure boats are sometimes stopped and their crews and passengers robbed and, on rare occasions, kidnapped. From $1 million to $2 million worth of fuel has been stolen from each of six tankers that have lost part or all of their cargos in the South China Sea since mid-April.