Pirates off the coast of Somalia made big news a few years ago. But the waters of the West Indian Ocean are not the world's most dangerous for pirate attacks right now. The most dangerous seas are those of Southeast Asia.

The International Maritime Bureau released a report on sea pirates this week. The IMB says more than half of all sea pirate attacks since the beginning of 2015 have been in Southeast Asia.

Pottengal Mukundan is the director of the IMB. He tells VOA that armed pirates attack small oil ships in the area about every two weeks.

Armed Robbery and Piracy Against Ships. (ICC International Maritime Bureau)

"It is a disturbing trend because if firm action is not taken then we expect that the violence will increase and the pirates will get a little more audacious in the kind of targets that they will look for."

The IMB director says the small tankers moving slowly along Southeast Asian coasts are also vulnerable because they sit low in the water.

"The hijackers approach the vessel in very fast skiffs. They take over the ship and then they siphon or steal part of the cargo on board - usually marine gas oil, diesel oil, that kind of product which can be very quickly disposed of locally."

Vietnam sees a rise in pirate attacks

Almost 40 percent of pirate attacks this year have been off the coast of Indonesia.

But armed robbery attacks are increasing around Vietnam. In the last three months, Vietnamese officials have reported eight incidents. Pirates are breaking into ships stopped in and around Haiphong and Vung Tau.

Pirates are leaving Somalia alone

In contrast, no incidents have been reported this year in Somalia. The last reported hijacking in those waters was in May 2012.

Officials say pirates are not attacking Somalia for several reasons. The country now has a functioning government, a multi-national naval patrol and anti-piracy measures, including onboard armed guards.

But Pottengal Mukundan of the IMB warns it would be very easy for the situation to return to the bad old days.

"All it takes is one successful hijacking and suddenly people will get interested once more in this criminal activity. So we've got to be watchful, the ships have got to be vigilant and we need the navies there."

I'm Jonathan Evans.

This report was based on a story from reporter Steve Herman. Marsha James wrote it for VOA Learning English. Kelly Jean Kelly was the editor

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