Pirates captured a Panamanian-flagged ship with 26 crew off the East Africa coast on Thursday and fired rocket-propelled grenades and automatic weapons at an Italian ship, which escaped.
The bulk carrier Al Khaliq was hijacked when pirates boarded and overpowered the mostly Indian crew in waters between Somalia and the Seychelles, the joint European Union-NATO mission to protect shipping in the region said.
"Within the last hour, an EU NAVFOR maritime patrol aircraft has confirmed the hijack of MV Al Khaliq, (with) six pirates on board and two attack skiffs in tow," it said.
"The mother skiff has already been taken on board with a crane," it added of the early-morning attack, 180 nautical miles west of the Seychelles.
A spokeswoman in London had earlier said "there were 26 crew on board, 24 of whom are Indian and two Burmese."
The Italian carrier Jolly Rosso managed to shake off its attackers in a dramatic incident off the Kenyan coast, which along with the hijacking hundreds of miles away, highlighted the difficulty for international naval forces scrambling to contain a huge upsurge in attacks this year.
Pirates aboard two small skiffs unleashed "automatic fire and also fired three rocket-propelled grenades" at the 22,000-tonne ship, 400 nautical miles east of Mombasa, the naval mission added.
But it managed to shake off its attackers by opening its throttles to 18 knots, the spokeswoman said.
"The ship took appropriate evasive action, managed to evade the attack and is proceeding on her voyage," said the statement.
"There were no casualties."
NATO's closest ship in the Somali basin was eight hours away from the Al Khaliq when it was seized. A Belgian warship has since been despatched to the area alongside a Seychelles coastguard vessel.
"We are working with coalition partners" from the EU, the US and other independent missions, the spokeswoman added.
Incidents off the coast of lawless Somalia rose to 47 during the first nine months of 2009 from 12 in the same period a year ago, the International Maritime Bureau (IMB) said Wednesday.
In the Gulf of Aden there were 100 attacks compared to 51.
Since last year a flotilla of foreign warships has been patrolling the piracy-plagued Gulf of Aden, one of the busiest maritime trade routes on the globe.
The Kuala Lumpur-based watchdog said that globally, 114 vessels were boarded and 34 hijacked during the first nine months of 2009. A total of 661 crew members were taken hostage, six were killed and eight are missing.
Attacks have recently risen again after a lull between July and September which the IMB attributes to monsoon conditions which make the seas too rough for pirates to operate in small boats.
In Brussels, the European Union's anti-piracy naval mission said a Chinese cargo ship seized in the Indian Ocean with 25 crew arrived on Thursday in waters favoured by Somali pirates.
"The hijacked bulk carrier the De Xin Hai is confirmed to have arrived off the coast of Somalia and is now in the vicinity of Hobyo," it said, adding it was unknown if the pirates had contacted the owners or made any demands.
Aircraft belonging to the European Union's Atalanta anti-piracy mission were monitoring the situation, it added, after Chinese state media said the vessel has enough fuel for a month and ample supplies of food and water.
In another development, the Seychelles said Thursday it was to deploy troops to some of its outer islands to deter Somali pirates that have been hunting their prey ever closer to the Indian Ocean archipelago nation. Pirate-hemmed Seychelles to deploy troops on remote isles
President James Michel "approved the immediate deployment of the Seychelles Peoples Defence Forces to the islands" situated north and south of the main island of Mahe, a statement from the president's office said.
With 115 islands scattered inside an exclusive economic zone spanning 1.4 million square kilometres and a population of only 85,000, the Seychelles has requested foreign assistance to stave off the pirates.