Somali pirates killed five crew members of an oil tanker they held captive for more than five months before security forces retook the vessel, authorities in Somalia’s semi-autonomous Puntland region have said.

The Palau-flagged MT Honour 25 was seized on April 21 with 17 crew members on board. Puntland authorities said 16 suspected pirates were detained during the operation to regain control of the vessel, while others escaped.

“Puntland Maritime Police Force (PMPF) has concluded an operation to secure the MT Honour 25. The vessel is now safe and under Puntland Government control,” the force said on X on Tuesday.

According to the PMPF, three of the five victims were Pakistani nationals, one was from Myanmar and another from India. Four other sailors – three Pakistanis and one Indian – were wounded. The tanker was carrying around 18,500 barrels of fuel when it was seized.

From 2008 to 2018, Somali pirates disrupted critical world waterways, causing widespread chaos. The new incident comes amid a resurgence in piracy off the coast of Somalia following years of relatively low activity. At least 15 attacks have been recorded in the region this year, according to an analysis of International Maritime Organization data, with Somali pirates successfully hijacking at least six commercial vessels since April.

Puntland forces regained control of the Eritrean-flagged oil tanker Sibu 1 earlier this month after it had been held by pirates for more than a month.

In August, Somali forces working with the Turkish Navy also retook the Cameroon-flagged cargo ship MV Lutuf after it was hijacked off Puntland. Somalia’s Defense Ministry said 14 suspected pirates were killed and four of their boats destroyed during the ten-day operation.

In an analysis published last week, the Royal United Services Institute (RUSI) linked the resurgence in piracy to turmoil in the Middle East, saying naval assets have been diverted from the Somali coast toward the Strait of Hormuz and Bab el-Mandeb. It also cited higher global oil prices as a factor that may have made hijackings more attractive. The spike has come during a year of major disruption to energy shipments from the Persian Gulf.

Countries in the region have stepped up maritime security cooperation amid the renewed activity. Russia and the Seychelles, an Indian Ocean island nation roughly 1,300 km southeast of Somalia, are planning joint anti-piracy exercises in November during a Russian Navy port call, Seychelles’ defense chief said on Saturday.