UAE-backed Yemeni separatists send more forces for Aden 'coup'
On Sunday, security sources said pro-separatist units trained and backed by the United Arab Emirates had taken over the government headquarters in Aden after clashes.
The fighting killed at least 15 people including three civilians, after separatist protesters were prevented from entering the city for a rally to demand the government leave Aden.
Yemen's President Abd Rabbo Mansour Hadi ordered his forces to cease fire immediately after fierce clashes, but fighting continued on Monday between government units and secessionists.
Separatists dispatched additional forces from the central province of Marib and southern province of Abyan, security sources said.
The forces from Abyan progressed towards Aden after clashes with government forces on the way, they said.
The International Committee of the Red Cross reported fighting overnight in Aden.
"All night shooting in Aden #Yemen, including heavy weapons," Alexandre Faite, the head of the ICRC delegation in the country based in Sanaa, said on Twitter.
"Those in southern part of city, including (ICRC staff) still unable to get out."
The separatist takeover on Sunday in the interim capital threw war-torn Yemen into further chaos, sparking warnings of a "coup" from the embattled government.
It further complicates years of conflict, in which the Saudi-backed government has been battling Iran-backed rebels controlling the capital Sanaa and much of the north of the country.
South Yemen was independent - with former British colony Aden as its capital - from its formation in 1967 until 1990, when it was unified with North Yemen.
More than 10,000 people have been killed in Yemen since a Saudi-led military coalition intervened to support Hadi's government in its fight against the rebels in 2015.