British forces freed an Italian cargo ship hijacked by Somali pirates after retrieving a message in a bottle tossed by hostages from a porthole.
The message inside confirmed that the crew was safely sealed inside an armoured area.
All 23 crew members of the Montecristo cargo ship were brought to safety and the 11 pirates arrested.
The crew, seven Italians, six Ukrainians and 10 Indians, locked themselves inside an armoured area of the vessel when the pirates boarded the ship, Italian Defence Minister Ignazio La Russa said. Safe from the pirates' threats, the crew continued to navigate the ship.
"The criminals managed to cut off all means of communication, but the 'prisoners' tossed a bottle with a message through a porthole explaining the situation," Mr La Russa told a news conference.
At that point, other ships in the area were aware that the Italian vessel had been boarded by pirates. But the message in the bottle gave an important signal the crew of the Italian ship were out of harm's way and that a rescue operation could be launched without risking injury.
"Rubber boats circled the Montecristo, while a helicopter hovered above. The pirates surrendered right away, some throwing their weapons in the sea, and were arrested," he said.
The pirates attacked the ship on Monday 620 miles off Somalia as the crew was hauling scrap iron to Vietnam on a journey that had begun on September 20 in Liverpool.
The operation was carried out by two ships - one Royal Navy and one American.
Britain's Defence Ministry said the RFA Fort Victoria "responded to calls to assist a pirated Italian merchant ship, the MV Montecristo, along with an American Navy frigate." Because of the presence of warships, the pirates on board surrendered without force, it said.
Pirates flourish off largely lawless Somalia by attacking passing ships, taking hostages and demanding ransoms to free them and the vessels.