MANILA (AP) — A torturous wait by the families of 23 captive Filipinos ended as Somali pirates freed a chemical tanker after holding the crew for more than five months in the Gulf of Aden.

Catherine Borretta broke into tears after receiving a cell phone message that her husband Rodell — a second mate on the Philippine ship MT Stolt Strength — was released with the others.

"I'm so overjoyed, so overwhelmed," Borretta said, adding she'll welcome Rodell with his favourite pork dish and a small party at home.

It was unclear if a ransom was paid for the release of the tanker and crew. Family members said the Somali pirates earlier demanded $5 million but the amount had been reduced to about $2.2 million last week.

One crew member needed medical attention but does not have a serious problem, NATO spokesman Lt-Cmdr. Alexandre Santos Fernandes said. The tanker will head to Mombasa, Kenya, arriving in about a week.

"They have been released, thank God!" said Doris Deseo, wife of Carlo Deseo, the ship's 31-year-old third mate. "They are no longer in the hands of the pirates. I am super happy."

At least 16 other ships with nearly 300 crew remain in the hands of Somali pirates, officials say.

The release came as an international maritime watchdog reported that attacks by sea worldwide nearly doubled in the first three months of 2009, mainly because of increased pirate raids on vessels in the Gulf of Aden and the east coast of Somalia.

Analysts blame Somalia's nearly 20 years of lawlessness for fuelling piracy's rise.

Attacks have risen markedly in recent weeks, including one Monday when pirates fired rockets at a Maltese-flagged ship off Yemen's coast.

NATO warships scrambled helicopters in defence and the pirates escaped with no damage to the cargo ship.

Yesterday's release came a day after a separate group of bandits freed the Lebanese-owned food aid freighter MV Sea Horse after receiving $100,000 from Somali businessmen.

The Stolt Strength was seized November 10 by pirates in the Gulf of Aden while it was carrying a cargo of phosphoric acid. Securing the safe release of the vessel and crew was "difficult and protracted," Sagana Shipping Inc. spokesman Dexter Custodio said in a statement.

Custodio said he could not comment on whether ransom was paid. "I have no idea because it was the company's crisis management team that has the data about that," he told The Associated Press.

Asuncion Pacheco, wife of 62-year-old ship captain Abelardo Pacheo, said she was told by a company official the amount of ransom paid to the pirates "will not be disclosed for the protection of the others," referring to other vessels still being held by the Somali gunmen.

During the five-month ordeal the families wondered if they'd ever see their loved ones again.

Some of the Filipino crew were able to call relatives

back home while in captivity. Two weeks ago Vilma de Guzmán received a call from her husband who said "goodbye" to her and their three children, just in case he did not survive.

The number of attacks in the Gulf of Aden surged to 102 in the first quarter of 2009 compared to 53 incidents in the same period a year ago.

It was also a 20 percent increase from the previous quarter, said the International Maritime Bureau's piracy reporting centre in Kuala Lumpur.

NATO forces have helped fend off several attacks in recent days, but have released the culprits because they had no jurisdiction to arrest them.

In some cases, neither the pirates nor their targets were nationals of NATO countries.

In Washington, U.S. Secretary of State Hillary Rodham Clinton and Dutch Foreign Minister Maxime Verhagen met Monday and said they will seek authority for NATO to arrest pirates.

Tuesday's release came as the sole surviving Somali pirate from the hostage-taking of an American ship captain arrived in New York on Monday to face charges in the attack.