DUBAI (Reuters) - A blast struck a military graduation parade in Yemen's southern town of al-Dhalea, Yemen's Security Belt forces said in a tweet on Sunday, in an attack witnesses said caused dozens of injuries or deaths.

No claim of responsibility was made.

The Security Belt forces are part of a southern separatist front in south Yemen, and are backed by the United Arab Emirates in a fight against Yemen's Iran-aligned Houthi group.

Witnesses told Reuters that a blast occurred near a guest platform during the parade and that dozens were injured or killed. They reported seeing bodies at the scene.

Yemen has suffered from almost five years of conflict since the Houthi movement ousted President Abd-Rabbu Mansour Hadi's government in late 2014. The coup drew military intervention in 2015 by a Saudi-led coalition, which includes the UAE, trying to restore Hadi's internationally recognized government.

The town of al-Dhalea is controlled by southern separatist forces. It lies on the main south-to-north road linking the southern port of Aden — controlled by Hadi's government — to the Houthi-controlled capital, Sanaa. A contested frontline runs across al-Dhalea province.