Sporadic attempts to hijack vessels continue to take place, though the limited resources pirate groups have access to these days don't stack up against the countermeasures they face.
"The EU Naval Force. has received positive confirmation from the master of".
The attacks dropped off following a coordinated worldwide response that included naval forces from North Atlantic Treaty Organisation, the European Union, the United States and other independent nations.
The Aris 13 oil tanker is seen from a helicopter in the harbor of Gladstone, Australia, on October 27, 2014.
An EU Naval Force photo shows the Aris 13 ship.
An official in the semi-autonomous Somali state of Puntland said more than two dozen men boarded the ship off Somalia's northern coast.
Pirate hijacks are usually carried out for ransom, but no ransom request has yet been made.
The Aris 13 sent a distress call on Monday, turned off its tracking system and altered course for the Somali port town of Alula, said John Steed of the aid group Oceans Beyond Piracy.
The eight crew members onboard are reported to be Sri Lankan nationals.
While the number of piracy incidents has fallen to almost zero in recent years, the threat of piracy in the region has persisted as numerous conditions that enabled piracy to flourish in the first place are still present.
The EU force website now lists no vessels or hostages held by pirates.
This effectively broke the pirates' business model as, until then, they had been able to approach a ship, often at dawn after a night of chewing the narcotic qat leaf, open fire on the bridge to scare the captain into slowing down and stopping, and then they would board it using ladders.
Hijackers had seized the ship about 30 km off the Somali coast.
Steed said the tanker which was carrying a cargo of gas and fuel was not registered with the Maritime Security Center for the Horn of Africa, an organization that registers and tracks commercial traffic in the region.
The ship is owned by a Panama-based company, Armi Shipping, and managed by Aurora Ship Management in the United Arab Emirates, according to the Equasis shipping data website. This is the first successful hijacking of a vessel by Somali pirates in three years, as pirate attacks declined steadily.
Nur, the local elder, told the AP that young fishermen including former pirates have hijacked the ship. Following the collapse of the government in the early 1990s, he says, foreign "fishing fleets came looting this place, and a lot of fishermen and fisherwomen were basically put out of business".