Suspected Somali pirates have hijacked two European-owned tankers within 24 hours in the highest-profile strikes since foreign navies deployed en masse to the region's busy sea lanes.
"These are the biggest attacks this year. The pirates are showing they are very much alive," said Andrew Mwangura of the East African Seafarers Assistance Programme, which monitors piracy in the region from the Kenyan port of Mombasa.
The 9,000-tonne MT Nipayia, a Greek-owned and Panama-registered ship with 19 crew on aboard, was taken on Wednesday 450 miles east of Somalia's south coast, the European Union and NATO said on piracy-monitoring websites.
The 23,000-tonne MT Bow Asir, a Norwegian-owned and Bahamian-registered ship, was seized on Thursday 250 miles east of the south Somali coast, they said.
The attacks show that Somali pirate gangs remain undeterred by a flotilla of ships from Western and Asian countries patrolling to try to prevent a repeat of last year's unprecedented wave of hijackings.
Most of those ships are, however, concentrated in the Gulf of Aden, the gateway to the Red Sea and Suez Canal, whereas the pirates are striking ever further from the Somali coastline.
In another long-distance strike this week, pirates hijacked a yacht from the Seychelles with two men on board. The boat was en route to Madagascar, well south of Somali waters.
"The naval operation is very successful in the Gulf of Aden," Pottengal Mukundan, director of the International Maritime Bureau piracy watchdog, told Reuters. "These attacks have taken place off the east coast of Somalia."
Citing information from other maritime organisations, Mwangura said the Bow Asir was carrying caustic soda, whereas the Nipayia was empty or "in ballast."
SOPHISTICATED TACTICS
Having made millions from ransoms in recent years, Somali pirate gangs are using increasingly sophisticated boats and radar equipments to spot, chase and capture other vessels.
"They are staying away from the security zone in the Gulf of Aden. They are trying to destabilise the security system the foreign navies have set in place," Mwangura said.
Typically, gangs operate from a "mother" ship that will launch faster speedboats, full of armed men, to board the target. Most crews surrender without a fight.
Two earlier high-profile cases were resolved earlier this year with the release -- for $3 million each -- of a Saudi oil tanker and a Ukrainian boat with tanks on board.
A record 42 boats were seized off Somalia throughout 2008, with a total 815 crew members taken hostage, according to figures from the International Maritime Bureau. Seven ships have been seized so far this year.
An increase in insurance costs has made some shipping firms go round South Africa rather than through the Suez Canal.
Mukundan said insurance costs had yet to come down because the number of attacks remained high, but he noted the proportion of successful hijackings had gone from 1 in 3 attacks in November to around 1 in 7 or 1 in 8 now.
Eager to protect some of the world's most important shipping lanes, the United States, various European nations, Russia, India, China and Japan have all sent ships to the waters.
"Once again, the Somali pirates are making fools of all of them," said a diplomat who tracks the piracy phenomenon.