World leaders are increasingly concerned by pirates operating off the coast of Somalia, who have seized several ships recently, demanding ransom payments to free them.
Warships from several countries have been sent to patrol the Indian Ocean, as the pirates are threatening some of the world's busiest shipping lanes.
Use the map to see how the pirates have affected various countries.
The so-called pirate capital of Somalia's Puntland region is where the high seas hijackers often steer their captured vessels. Special restaurants in the town cater for the captive crews. With their expensive tastes in fancy houses, cars and women, the pirates have brought boom times to the local economy.
A number of pirates have pounced close to the Yemeni shores but it is not known if any are actually based there. The gangs have been known to seize Yemeni fishing boats and use them to fool naval patrols. The pirates are believed to source much of their heavy weaponry, like rocket-propelled grenades, from Yemen.
Ethiopia is another source - albeit indirect - of arms such as AK-47s for the pirates. Somalia's Horn of Africa neighbour is known to have provided Somali clan militias with weapons to take on radical Islamists, although many of the firearms end up on sale in markets throughout Somalia.
The business capital of the world's maritime industry, London is home to many of the lawyers, negotiators and security teams who help reunite ship owners with their seized vessels. Legal advisors and maritime risk consultants help haggle over ransom fees while hired muscle ensures the cash reaches the raiders.
France has led the way in taking tough action against the pirates. In the past year French forces have captured more than 70 Somali pirates, and killed three others.
Wealthy businessmen in the emirate, which has a large Somali community, are suspected of having funded the pirates in the past through the informal Islamic finance system of Hawala. They also provided equipment like speedboats and GPS devices. But the pirates are now thought to largely manage their own affairs.
Kenya is trying a number of the Somali pirates currently in detention. Many of the captured ships have either been going to, or coming from, its main port of Mombasa. These include ships delivering food aid to Somalia.
US engagement with the issue of Somalia piracy escalated after two of its vessels were attacked. Secretary of State Hillary Clinton has announced a four-point plan for dealing with the pirates, including improving the situation in Somalia and freezing pirates' assets. One pirate, captured by US forces, is to be tried in the US.
Mogadishu is the capital of a nation which has been without an effective government since 1991. Islamist insurgents are battling a weak, internationally recognised government. The anarchy and fighting on the land has now spread to Somalia's waters. Mogadishu also has a large weapons market.
Every year, 22,000 ships pass through the Gulf of Aden to or from the Indian Ocean, carrying about 8% of the world's trade. Since piracy has escalated, at least nine countries have sent naval vessels to patrol the region. But the task is extremely difficult, because of the huge area within which the pirates operate.