No claim of responsibility was made and Houthi media did not immediately comment on the blast or accusation.
The missile blast struck a parade ground where a military graduation for Security Belt forces had just finished, statements from the Security Belt group and the al-Dhalea southern separatist forces said.
The Security Belt forces are part of a government-aligned southern separatist front in south Yemen which favors the creation of an independent state.
They are also backed by the United Arab Emirates in a fight against Yemen’s Iran-aligned Houthi group.
Witnesses told Reuters that the blast occurred near a guest platform during the parade, causing injuries and deaths. They reported seeing bodies at the scene.
Pictures from the scene showed a blast hole in the concrete floor of an outdoor square.
Six people died and between 15 and 25 were injured, according to local health authority figures quoted by the local forces’ spokesman.
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