A chronology of key events
Three ships held captive by Somali pirates are moved after Islamist insurgents seize one of their bases.
Islamist insurgents take control of one of the main pirate havens in central Somalia.
The UN Security Council unanimously adopts a resolution aimed at making it easier to prosecute and imprison Somalia pirates.
As a suspected pirate is shot dead by private guards repelling an attack off Somalia, should merchant ships be equipped for gun fights?
Somali pirates hijack a ship 1,800km off the African coast - closer to India than Africa, says the EU's naval force.
Somali pirates have released a chemical tanker and its North Korean crew of 28, maritime officials say.
Somalia's president says efforts are being made to release a Kent couple held by pirates at the "earliest possible date".
The French navy captures 35 Somali suspected pirates in three days - calling it the biggest seizure since 2008.
Pirates have hijacked a tanker and are sailing it towards the Somali coast, the ship's Norwegian owners say.
Pirates in Somalia free a Greek-owned cargo ship and its crew of 19 after a ransom is paid, officials say.
The British Somali community is keen to show its support for kidnapped Britons Paul and Rachel Chandler.
Somali pirates free a Taiwanese fishing boat held for 10 months after the owner pays a ransom, a maritime agency says.
Danish troops serving with Nato's anti-piracy force free the crew of a cargo ship boarded by gunmen off Somalia.
Somali pirates release the Greek-owned cargo ship Filitsa and its crew of 22, held since November, after a ransom is paid, officials say.
A UK-flagged cargo ship with 25 crew, including eight Bulgarians, is hijacked off Somalia, the second in a week.
A senior Chinese naval officer has suggested that China establish a permanent base in the Gulf of Aden.
The crew of a Chinese ship hijacked by pirates off Somalia have been rescued, officials say amid reports of a ransom.
Two British hostages being held by pirates in Somalia face a Christmas in captivity with no immediate sign of their release.
A group of suspected Somali pirates held on a Dutch warship are freed because the EU cannot find a country to prosecute them.