At least three vessels have been targeted in hijackings this week off the coast of Somalia in what analysts fear is a replay of past piracy around the Horn of Africa.

The area was the world’s most notorious hotspot for piracy in the early to mid-2000s, with an international naval coalition eventually subduing the threat it posed to global shipping.

According to the World Bank, the annual impact of piracy off Somalia on the global economy was as high as $18bn during the height of the crisis.

Intermittent hijackings have continued since then, with a number of incidents occurring in the area this year.

However, the quick succession of tankers seized in recent weeks has further raised concerns.

The United Kingdom Maritime Trade Operations (UKMTO), which provides security information about trade routes to shipping firms, raised the threat levels around the Somalia coast to “substantial” this week and warned vessels to “transit with caution”.

Here’s what we know about the recent hijackings:

What has happened?

Three to four merchant ships are believed to have been captured close to the coast of Somalia since April 20.

The European Union Naval Force (EUNAVFOR) said it had been alerted by the Puntland Maritime Police Force (PMPF) of the hijacking of the fishing vessel Alkhary 2 on April 20.

Media reports noted that a Somali-flagged fishing vessel was taken around the coast in northern Somalia and was later released.

The next day, EUNAVFOR reported that another vessel, Honour 25, had been seized in the same area. Media reports say six pirates targeted the tanker loaded with approximately 18,000 barrels of oil off the coast of the semi-autonomous state of Puntland. It is believed to be anchored between the fishing villages of Xaafuun and Bandarbeyla, with five more pirates on board since its hijack.

The ship had first sailed to the United Arab Emirates, but had to turn back towards Mogadishu on April 2, after which it failed to enter the Strait of Hormuz. It had 17 crew members on board, including people from Pakistan, Indonesia, India, Sri Lanka and Myanmar, according to the BBC.

EUNAVFOR on Tuesday said its patrol assets had surrounded the vessel.

On April 22, the PMPF reported that Alkhary 2 had been released and all crew members were safe, but that the “Pirate Action Group” remained on board Honour 25.

On April 26, EUNAVFOR said it was monitoring the hijacking of another merchant vessel, the Sward.

UKMTO reported that the Sward had been hijacked 6 nautical miles (11km) northeast of the Somali coastal town of Garacad. The British ⁠maritime security group Vanguard said the ship’s 15-person crew comprised two Indian nationals and 13 Syrians.

The following day, Puntland officials revealed that a vessel carrying cement and flying the flag of St Kitts and Nevis had been hijacked off the coast of Garacad, in the Puntland region. It is believed to have also been referring to the Sward. The vessel had left Egypt for Kenya’s Mombasa, authorities said, and nine armed pirates were on board.

Who is behind these hijackings, and what’s behind the new surge?

It is yet unclear which groups are behind the attacks. In the past, local fishermen and various armed groups, including those affiliated with ISIL (ISIS) and al-Qaeda, have been involved in hijackings.

Analysts speculate that the diversion of antipiracy patrols since 2023 to the Red Sea to counter attacks by the Yemen-based Houthis in the Bab al-Mandeb Strait, which connects the Gulf of Aden with the Red Sea, has created an opportunity.

More recently, naval patrols of some nations that previously helped contain the threat of piracy have been distracted or diverted towards shepherding ships trying to access the Strait of Hormuz, which Iran and the United States have blocked.

The surge in petrol prices amid the US-Israel war on Iran has also likely made fuel tankers, such as the Honour 25, more valuable to pirates, experts say.

Brent crude prices — the global oil benchmark — have risen by more than 50 percent since the start of the war, and are at more than $110 per barrel.

What is the history of piracy on the coast of Somalia?

Piracy has long been rife off the Somali coast, in the Gulf of Aden, and further into the Indian Ocean. In the early 2000s, hijackings escalated as the Somali government collapsed during the Somalia-Ethiopia war of 2006-09.

Thousands of seafarers were captured or fired at, with pirates demanding millions of dollars in ransoms. The World Bank estimated that from 2005 to 2012, ransoms totalled between $339m and $413m.

In 2011 alone, about 212 attacks were recorded – one of the highest numbers in a single year.

An international coalition composed of NATO’s Operation Ocean Shield, EUNAVFOR Operation Atalanta, the Combined Maritime Task Force, and the Somali authorities began patrolling the area. The patrols and the 47-country naval partnership helped to reduce attacks drastically.

EUNAVFOR, along with the Somali authorities, has continued to oversee antipiracy operations in the area.