The UK has warned of small ships acting suspiciously in the Gulf of Aden, days after an attempted ship hijacking suspected to have been carried out by Somali pirates.

The UK Maritime Trade Operations (UKMTO) said it had received “numerous reports” from ship masters of suspicious activity by small craft at the entrance to the Red Sea, without going into detail.

Intelligence firm Diaplous Maritime Services later said a flotilla of 10 “Yemeni type” skiffs had been spotted by an armed team onboard a vessel in the International Recommended Transit Corridor.

There was no escalation and the unnamed vessel was able to continue its voyage.

The UK warning will add to concerns that another attack on shipping around the Gulf of Aden could be in the making, amid confusion over whether an attempted hijacking of Zodiac Maritime’s 20,000-dwt Central Park (built 2015) was related to Houthi militant activity against Israeli-linked ships.

The US military claimed that the Gulf of Aden attack on the tanker at the weekend was probably carried out by Somali pirates and was not part of recent targeting of Israeli ships in the Red Sea by Yemen’s Houthi militants.

However, Somali piracy has virtually been eradicated in recent years. After the attempted boarding, the Central Park’s attackers fled towards Yemen, rather than Somalia, security sources told TradeWinds.

The confusion is adding to tensions in the region following the capture by Houthis of Ray Car Carriers’ 5,100-ceu Galaxy Leader (built 2022) in the Red Sea and a drone attack on the 15,300-teu CMA CGM Symi (built 2002), owned by Eastern Pacific Shipping.

War risk insurance rates in the Red Sea have already skyrocketed for Israeli-linked ships, although they remain more stable for other shipping.

Following the attacks, AP Moller-Maersk diverted two Israeli-linked container ships, the 4,256-teu Lisa (built 2009) and 5,295-teu Maersk Pangani (built 2021), away from the region.

Israeli container ship operator Zim is also diverting ships, as is Ray Car Carriers.