DUBAI, United Arab Emirates (AP) — A ship came under attack Friday off the coast of Yemen in unclear circumstances, a British military organization said.

The British military’s United Kingdom Maritime Trade Operations, which provides support to ships across the Mideast, said the attack happened off Nishtun, Yemen, in the country's far east near the border with Oman.

It said shots had been fired at the unidentified vessel in the Gulf of Aden, with three boats chasing after it.

There was no additional information immediately available.

The Gulf of Aden is a crucial route for global trade and has seen attacks attributed to Yemen’s Iranian-backed Houthi rebels as its civil war rages. Somali pirate attacks that once plagued the region have mostly stopped in recent years.

Nishtun is held by forces allied to Yemen's internationally recognized government, which is backed by a Saudi-led coalition.

However, attacks have happened there before. In December 2020, a mysterious attack targeted a cargo ship off Nishtun. In Yemen's war, bomb-carrying drone boats, as well as sea mines, have been used.

The attack comes after Iran separately seized an oil tanker Thursday carrying crude for Chevron Corp. on its way to Houston.