A United Nations vessel delivering humanitarian aid to the Yemeni port of Hudaydah has come under a suspected Saudi attack.

Yemen’s Red Sea Ports Corporation said on Monday that the vessel used by the UN’s World Food Programme (WFP) was attacked after delivering a shipment at Hudaydah, a port in western Yemen which is controlled by the ruling Houthi Ansarullah movement and is under a blockade by Saudi Arabia and its allies fighting the Houthis.

“The vessel traffic office received a distress call from the VOS THEIA at 1730 (1430 GMT) on Sunday, June 3, 2018 about a fire in the vessel resulting from an external attack,” said the Port Corporation in a statement, although it would not elaborate on who might have launched the attack.

The statement added that the ship was waiting in anchorage for permission to leave when it came under attack.

The UN’s aid chief, Mark Lowcock said, however, that no one was injured and the situation was calm now.

“There was an incident ... We don’t know who’s responsible. We’re investigating and the incident is over,” said Lowcock.

This photo taken on January 11, 2018, shows UN Under-Secretary-General for Humanitarian Affairs Mark Lowcock. (Photo by AFP)

The UN official, however, criticized anyone seeking to disrupt the humanitarian aid delivery in Hudaydah, a port which handles the bulk of Yemen’s commercial imports and aid supplies and is regarded as a lifeline for some eight million Yemenis being fed by the UN.

“There’s no port more important than Hudaydah. So anything which called into question the operation of Hudaydah would be a matter of deepest concern,” he said.

Reports over the past weeks have indicated that Saudi Arabia and its allies have been advancing on Hudaydah, launching frequent attacks on port authorities and guards patrolling at sea.

Saudis refused to provide any comment on the incident involving the UN aid boat.

According to figures released by the Yemeni Ministry of Human Rights, more than 600,000 people have been killed or injured in the Saudi war since 2015.

The illegal campaign, which is meant to restore power to former president Abd Rabbuh Mansur Hadi, has also displaced hundreds of thousands of Yemenis while exacerbating the humanitarian plight of millions already affected by poverty and malnutrition in the Arabian Peninsula’s poorest nation.