The last shipping hostages have been freed by Somali pirates, marking an end to a decade of terror inflicted on the industry.

The trio were taken from an Iranian fishing vessel called Siraj in March 2015.

Since 2010, Somali gunmen have held more than 2,300 seafarers in captivity through abductions or hijackings, but successful attacks have tailed off to zero in recent years as world navies came together to combat the threat, together with armed guards on vessels.

"This marks the end of an era of Somali piracy and the pain and suffering of Somalia's forgotten hostages," John Steed, coordinator of the Nairobi-based Hostage Support Programme (HSP), told Reuters.

The former British army officer has spent years negotiating the release of hostages in Somalia.

The freed men were "very thin as expected" and have gastric problems, but are otherwise okay, Steed said.

Death, torture and trauma

HSP said in a statement: "Between 2010 and 2019, Somali pirates held over 2,300 crew either captive on their ships or as hostages.

"Many were tortured, some died but all were traumatised by their experiences. We are only glad that we have been able to rescue all those who were left behind and fell outside the normal reaches of companies and countries."

At the peak of the scourge in 2011, the gangs launched 237 attacks, according to the International Maritime Bureau (IMB).

A report last week suggested that the threat of Somali piracy may have raised its head again, following an "attack" on the 8,143-dwt tanker Aegean II (built 1994) after it developed mechanical issues.

But later intelligence reports revealed this was an incident where local police boarded the vessel over an alleged pollution incident.

Security consultancy Ambrey verified that a sheen, possibly an oil spill, could be seen in the vicinity hours before the incident.

"However, there is no evidence this was caused by the tanker," Ambrey said.