The attack came as southern separatists battled Yemeni government forces for control of the interim capital of President Abd-Rabbu Mansour Hadi's government in Aden. Separatists stopped outside the al-Maasheeq palace, where Prime Minister Ahmed bin Daghr's government is based.
According to the news wire, Reuters, the prime minister and senior government figures are trapped inside the palace.
The internationally recognised government of Yemen has been fighting for almost three years to regain control of the country after losing the capital Sanaa and much of the north to the Houthi rebels.
The International Committee for the Red Cross (ICRC) said late on Monday that at least 36 people have been killed and 185 others wounded in two days of fighting in Aden.
The seizure of the military base, which is located in Aden's northern Dar Saad district, is the largest gain for the separatist group since fighting began Sunday.
The Interior Ministry sent an urgent appeal to the Saudi-led coalition, asking for its intervention to stop attacks by the STC forces.
In the past months, government forces and the UAE armed forces operating in Aden province launched an anti-terror offensive to root out Al Qaeda militants from their strongholds in the neighbouring province of Abyan.
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Last year, the European Commission announced that it had launched an investigation into Ikea's tax deals in the Netherlands . His decision to live overseas , mainly in Switzerland , to avoid Sweden's high income taxes was also widely criticised.
He urged a Saudi-led military coalition backing Hadi to intervene in its defence.
Why has this happened: Hadi and the UAE, which are both part of the Saudi-led coalition, have been locked in a long-running power struggle.
Separatists have dispatched additional forces from the central province of Marib and the southern province of Abyan, security sources said.
A fighter from the separatist Southern Transitional Council walks with smoke billowing in the background in the government's de facto capital Aden, as they move closer to taking full control of the southern city, yesterday.
Yemeni President Hadi in Riyadh hold a meeting with his assistants on Monday night, describing the events in Aden as a "coup against the legitimacy".
Yemen was unified militarily in 1990 after a protracted war, but an active secessionist movement remained in and around Aden ever since, and they appear to have finally found an opening to reassert themselves.