Nairobi - Somali pirates achieved a new milestone in their seemingly unstoppable rise this weekend when they seized a Saudi Arabian supertanker laden with two million barrels of oil worth almost 100 million dollars.

It seems that every month there is a new first for the pirates, who have dramatically increased the frequency of their attacks this year.

But what is most concerning about the latest attack is that it seems to point to the pirates changing tactics in response to an increased presence of international warships in the region.

In August, pirates seized four ships within 48 hours. Then, in September, they seized a Ukrainian freighter bristling with weaponry, including 33 Soviet-era tanks intended for Kenya - or South Sudan, depending on whom you believe.

In total, according to the International Maritime Bureau (IMB), there have been 92 attempts at piracy off the coast of Somalia this year, 36 of them successful. Fourteen ships are currently being held, along with 268 crew.

Usually the pirates confine themselves to the Gulf of Aden, a relatively narrow shipping channel which forms part of the route linking the Indian Ocean with the Mediterranean Sea through the Suez canal, and its environs.

But the seizure of the 330-metre Sirius Star took place in the open ocean some 450 nautical miles southeast of the Kenyan coastal city of Mombasa.

"We are concerned ... for pirates to come so far out, this means they can then go to any part of the ocean to hijack ships," Noel Choong, head of the IMB's Kuala Lumpur-based Piracy Reporting Centre, told Deutsche Presse-Agentur dpa.

International warships have flocked to the area in response to the surge in pirate attacks.

Warships from the North Atlantic Treaty Organization, Russia, the US-led coalition forces and France are patrolling the Gulf of Aden. The European Union has also authorized a force of five to seven frigates, which is expected to arrive in December.

The pirates, who launch speedboats from a mothership and are equipped with Global Positioning Satellite technology (GPS), automatic weapons and rocket-propelled grenades, appear undaunted. They are just going further afield in search of multimillion-dollar ransoms.

"Warships are patrolling the Gulf of Aden and we are advising ships to keep their distance from the Somali coast," Choong said. "That could one of the reasons the pirates are going so far out."

With big-money ransoms on offer, it is little wonder the pirates are not ready to give up easily.

A report released by London-based independent think tank Chatham House in October said that pirates had scooped up to 30 million dollars from ransoms in 2008.

The pirates are helped by the fact they have a huge area to operate in. The US Navy's 5th fleet, which operates a security patrol in the area, has said that even the Gulf of Aden is too large to patrol 100 per cent.

Choong is worried that if the pirates continue to head out to open sea then naval forces will not be able to counter the problem.

"I don't think there are enough warships to patrol," he said. "Even the Gulf of Aden is just too wide and too long. If you look at east and south Somalia, the sea is open. It is nearly impossible to patrol this area."

The US Navy believes that many of the attacks could be avoided and that shipping companies should take on more responsibility.

"One of the things we have tried to do with the recent spike in activity is to ensure that shipping lines understand the proactive measures they need to take in order to protect their ships, crew and cargo," Commander Jane Campbell, a Bahrain-based spokeswoman for the US Navy's 5th fleet, told dpa.

According to the 5th fleet, at least ten out of 15 recent pirate attacks in the Gulf of Aden involved ships travelling outside the IMB's recommended traffic corridor or failing to employ "recommended self-protection measures."

The simplest strategy for many shipping firms may be to simply avoid the route altogether, instead rounding the Cape of Good Hope to circumvent Africa.

Independent London-based think tank Chatham House warned in October that this would begin happening, thus increasing delivery times and the price of commodities and oil.

Its prediction now seems to be coming true. Norwegian shipping company Odfjell SE on Monday said it would begin to reroute its ships to avoid attacks.

But according to Chatham House, insurance premiums for ships sailing through the Gulf of Aden have also increased tenfold this year, so whether companies choose to switch routes or not, the cost of shipping, which is passed onto the consumer, is increasing.

Many feel that to address the problem, lawlessness in Somalia must be curbed.

The surge in piracy has coincided with a rise in violence in Somalia itself, where authorities in the central and southern region are battling a bloody insurgency.

The weak central government has been unable to suppress either the insurgency or the growing piracy.

Choong believes only the international community can solve the problem.

"The only way is for the United Nations and international community is to take action to stop the attacks," he said. "There needs to be political will." (dpa)