Mourning southern separatists clashed on Wednesday with presidential guards in Aden, the seat of Yemen's government, with one person killed and at least two badly injured, local officials and residents told Reuters.
The violence highlighted a rift within the Saudi-backed coalition battling the Iran-aligned Houthi movement in a four-year war that has killed tens of thousands of people and pushed Yemen to the brink of famine.
The separatists and the internationally recognized government of President Abd-Rabbu Mansour Hadi are nominally united in their battle against the Houthis.
But they have rival agendas for Yemen's future, and a missile strike in Aden last week killing 36 southern soldiers raised frictions between them.
Hundreds of separatist supporters attended a funeral for some of those troops and a prominent commander on Wednesday.
The funeral took place near the hilltop presidential palace and shooting was exchanged between presidential guards and the crowd which was chanting anti-government slogans.
After the funeral, a separatist leader called for people to march on the palace and overthrow the government, though there was no sign such a march had begun.