Members of Sudan's cabinet and a large number of pro-government party leaders were arrested on Monday in an apparent coup after weeks of tension between the military and a civilian government, political sources said.
Here is some background to the events.
WHO IS IN CHARGE IN SUDAN?
Sudan began a transition to democracy after a popular uprising and the ouster in April 2019 of President Omar al-Bashir, an Islamist shunned by the West who had presided over the country for nearly three decades.
Under an August 2019 agreement, the military is sharing power with officials appointed by civilian political groups in a ruling body known as the Sovereign Council, meant to lead the country to elections by the end of 2023.
HAVE THERE BEEN TENSIONS BEFORE?
Although the military's role is supposed to be largely honorary, civilians have repeatedly complained of military overreach in foreign policy and peace negotiations.
The military has accused civilian parties of mismanagement and monopolising power. A coalition of rebel groups and political parties have aligned themselves with the armed forces and have sought to dissolve the civilian cabinet.
Authorities said in September they had foiled an attempted coup, accusing plotters loyal to Bashir.
WHAT ARE THE DISAGREEMENTS OVER?
One point of tension is the pursuit of justice over allegations of war crimes by the military and its allies in the conflict in Darfur from 2003. The International Criminal Court (ICC) is seeking trials for Bashir and other Sudanese suspects. The cabinet has signed off on handing over suspects, but the Sovereign Council has not.
Another is an investigation into the killings of pro-democracy protesters on June 3, 2019, in which military forces are implicated. Activists and civilian groups have been angered by delays in making the investigation's findings public.
Civilians have also pushed for oversight and restructuring of the military, particularly through the integration of the powerful, paramilitary Rapid Support Forces, which military leaders have resisted.
WHAT ABOUT THE ECONOMY?
A worsening economic crisis that sent the currency plunging and created frequent shortages of bread and fuel was the trigger for Bashir's downfall.
The transitional government has implemented harsh, rapid reforms monitored by the International Monetary Fund in a successful bid for debt relief and to attract foreign financing.
In the wake of the reforms, inflation rose to historic highs of more than 400% and many Sudanese complain of struggling to get by. There have been occasional protests over economic conditions.
HOW ARE RELATIONS WITH THE NEIGHBOURS?
Sudan is in a volatile region, bordering the Red Sea, the Sahel, and the Horn of Africa. Several of its neighbours, including Ethiopia, Chad and South Sudan have been affected by political upheavals and conflict.
Since late last year, conflict in Ethiopia's Tigray region has pushed tens of thousands of refugees into eastern Sudan and caused military tensions in disputed agricultural lands along the border.
Sudan is pushing, with Egypt, for a binding deal over the operation of a giant hydropower dam that Ethiopia is building near the Sudanese border. Talks have stalled but Ethiopia has started filling the reservoir behind the dam, which Sudan says could put its citizens, dams and water facilities at risk.