Somali pirates who seized a Comoros-flagged oil tanker earlier this week after five years without a major Sea Piracy off the Indian Ocean have released the ship and its crew without conditions, officials said late Thursday.

Security official Ahmed Mohamed told The Associated Press the pirates disembarked the ship, which was heading to Bossaso port, the region's commercial hub, with its eight Sri Lankan crew members aboard. Monday's hijacking of an oil tanker off Somalia's northern coast surprised the international shipping community after several years without a pirate attack on a large commercial vessel there. Naval patrols by NATO members and other countries like China had calmed the crucial global trade route that once saw hundreds of attacks.

But people in this sleepy village saw something like this coming. Some are former pirates themselves who quit in recent years as the international pressure grew and armed guards appeared on cargo ships. They turned to fishing but now say they're the ones being targeted at sea.

In recent years, local officials have warned that rampant over fishing by foreign trawlers was destroying the livelihoods of Somali coastal communities, stoking fears of a return of piracy as a way to make money to secure their way of life. They have blamed Yemeni, Chinese, Indian, Iranian and Djibouti-flagged fishing boats and trawlers.

“The illegal fishing is a very serious problem. Fishing has declined, equipment was confiscated and they destroyed our livelihoods and properties,” said Aisha Ahmed, a fish dealer. The chairman of the fishermen's association, Mohamed Saeed, said frustrations are growing. “They have no choice now but to fight,” he said.

Somalis say illegal, unlicensed, and unregulated fishing forced them to turn to piracy 10 years ago in order to recoup their losses. "We got fed up and took guns to the sea," said one Bosaso fisherman, Mohamed Adan Ahmed.

The hijacked oil tanker was anchored Tuesday off the town of Alula, local elder Salad Nur told The Associated Press. He said young fishermen, including former pirates, had gone searching for a foreign ship to seize out of frustration.

“Foreign fishermen destroyed their livelihoods and deprived them of proper fishing,” he said.

The armed men were demanding a ransom for the ship's release and were holding the crew captive, the European Union anti-piracy operation off Somalia said late Tuesday after making contact with the ship's master. Illegal fishing needs addressing, said John Steed, the director of Oceans Beyond Piracy. “It's an aggressive business and in some cases international fleets pressure, even attack, local fisherman, which breeds resentment,” he wrote in an email.

“We have a famine and food is short. Fish is one answer,” he said, referring to the drought that Somalia recently declared a national disaster. “Fishing communities are angry and out-of-work fishermen have become - and are - pirates.”

In December, NATO ended its anti-piracy mission off Somalia's waters because there was no piracy for the past 4 years. Abdirizak Mohamed Ahmed, the director of the Anti-Piracy Agency in northern Somalia's semi autonomous state of Puntland, said he wasn't surprised by Monday's hijacking. The Incident happened in the Northern Puntland state.

Ahmed said fake fishing licenses issued to foreign fishermen and lenient enforcement of regulations by local authorities are major factors in the increase of illegal fishing. Fishermen have reported several cases of attacks by illegal fishermen, including close-ramming of their boats by trawlers. One fisherman died and another was seriously injured after a trawler ran over a small skiff off the coast early this month, Ahmed said.

Local fishermen also have reported incidents of foreign fishermen opening fire at them or robbing them of their catches before being chased away.

“It's matter of life and death. Now we have to fight at any cost,” Bile Hussein, a Somali pirate commander, said Tuesday, after the new hijacking was reported. He said he was in contact with the armed men on the seized oil tanker and that they had not yet decided on how much ransom to demand.

The ship in the Monday’s incident was owned by Flair Shipping Trading FZE in the United Arab Emirates and linked to UAE-based ship management firm Aurora Ship Management FZE. It was flying under the flag of Liberia at the time. It was not immediately clear if the companies were still linked to the ship.

Argyrios Karagiannis, the managing director of Flair Shipping, declined to comment. Calls and emails to Aurora went unanswered.

Concerns about piracy off Africa’s coast have largely shifted to the Gulf of Guinea.