Attacks from Houthi-controlled Yemen struck two Liberian-flagged ships in the Bab al-Mandab Strait on Friday, a US defence official said, underlining the threat to vessels in shipping lanes being targeted by the Iran-aligned group.

A projectile, believed to be a drone, struck one of the vessels, the German-owned Al Jasrah, causing a fire but no injuries, the official said. Two ballistic missiles were fired in the second attack, one of which struck a vessel, causing a fire that the crew was working to extinguish, the official said.

A US Navy destroyer was on its way to aid the vessel, the official said, without naming the vessel.

There were no immediate claims of responsibility.

Yemen’s Iran-aligned Houthis have been attacking vessels in Red Sea shipping lanes and firing drones and missiles at Israel since the start of the Israel-Hamas war in Gaza, in a campaign they say aims to support the Palestinians.

A spokesperson for Hapag-Lloyd, the company that owns Al Jasrah, said it was attacked while sailing near the Yemeni coast. “Hapag-Lloyd will take additional measures to secure the safety of our crews,” the spokesperson added, declining further comment.

At least two other shipping incidents were reported in the area on Friday.

British maritime security firm Ambrey said a Liberia-flagged container ship, MSC ALANYA, was ordered to alter course towards Yemen by people aboard a small craft assessed to be members of Yemen’s Houthi movement, forcing it to take evasive measures.

A spokesperson for MSC said there was no attack on the vessel and had no further comment.

Ambrey said the MSC ALANYA was warned by the Houthis not to proceed northbound, and quoted them addressing the crew: “Captain you are not allowed to proceed to the Red Sea. Alter your course to the south side, now”.

In another incident, Ambrey reported that the Liberia-flagged, Swiss-owned containership MSC PALATIUM III was targeted while sailing northbound some 23 miles southwest of the Mokha.

A spokesperson for MSC declined to comment when contacted about the report.

Ambrey said the vessel, which was en route to Saudi Arabia, had received the same warning as the ALANYA. It did not say who had targeted it. The Houthis, who rule much of Yemen, have vowed they will continue with their attacks until Israel stops its offensive in the Gaza Strip.