Nairobi - Crew members of the Maersk Alabama, whose captain Richard Phillips was freed from the clutches of Somali pirates in a dramatic Navy operation, paid tribute to their captain Monday and called on President Barack Obama to tackle piracy off the coast of Somalia. US Navy snipers on Sunday shot dead three Somali pirates who had been holding Phillips in a lifeboat since Wednesday, following a failed attempt to seize the Alabama.

A fourth pirate - who was on a US Navy ship, the USS Bainbridge, to negotiate Phillip's release at the time of the shooting - is in custody.

Captain Phillips has played down his part in the drama, instead praising the Navy Seals that freed him.

However, at a press conference in the Kenyan port of Mombasa, where the Alabama docked on Saturday, the crew hailed Phillips as a hero.

"Everyone you see here today has the captain to thank for their lives and their freedom," Chief Mate Shane Murphy said.

Phillips is on board the USS Boxer, one of three US vessels that rushed to the scene of the hostage drama, recovering from the five-day ordeal and being debriefed.

The drama began to unfold on Wednesday, when four armed pirates boarded the Alabama using grappling hooks.

Crew members forced the pirates to retreat to the Alabama's lifeboat with Phillips, who the crew said gave himself up as a hostage to safeguard the lives of his 19 American crew.

The pirates were quickly hemmed in by warships, part of a coalition force based in the Gulf of Aden, as negotiations to free Phillips got underway.

Phillips failed in an attempt to swim to the Bainbridge on Thursday and was tied up to prevent further escape plans.

He was only freed when the on-scene commander judged that Phillips' life was in imminent danger and ordered snipers to open fire from the Bainbridge.

The order to open fire if Phillips was under threat came directly from President Obama.

Murphy asked Obama to tackle Somali pirates, who have been wreaking havoc in the Gulf of Aden and surrounding region for years.

"We'd like to implore President Obama to use all of his resources to increase the commitment to end the Somali pirate scourge," Murphy said.

However, there are fears that the high-profile operation may raise the stakes, leading to pirates to become more violent.

Some pirate groups have already vowed to avenge their colleagues and to kill any American hostages taken in the future.

Two other pirates and one hostage were killed on Friday when French naval forces stormed a yacht, freeing four hostages.

Piracy has spiked in recent weeks after a brief lull due to bad weather.

In 2008, pirates seized over 40 vessels in and around the Gulf of Aden and collected tens of millions of dollars in ransom,s prompting the international community to send warships to the region.

Around 15 warships from the European Union, a US-led coalition task force and individual countries such as Russia, India and China patrol an area of about 2.85 million square kilometres.

However, the pirates are now venturing farther into the Indian Ocean off the south-east coast of Somalia to avoid the international patrols.

Pirates have attacked 18 ships over the last three weeks, according to the US Navy. Five of those ships are in pirate hands, joining eight others that have been held for months.

Over 200 seamen are being held by pirates.

The latest ship to be taken was an Italian tugboat, The Buccaneer, which was seized on Saturday. It has 16 crew members on board, including 10 Italians.

Reports said that the boat was spotted off the Somali coast near the pirate stronghold of Eyl on Monday.

Ship owners are being encouraged to take defensive measures, and there is a growing debate about reviving the practice of arming crew members on commercial vessels.

International observers, however, have long said the only way to nip piracy in the bud is to sort out the unholy mess that is Somalia, which has been without a functioning government since 1991 and is plagued by lawlessness. (dpa)