A political crisis in The Gambia appears to be coming to a head, with Senegalese troops massing on the border as a deadline for President Yahya Jammeh to step down came and went without any apparent change of heart from him. Mr Jammeh has refused to admit defeat in last month's elections and is still trying to hold on to his position. What happens next?
Why are there troops on the border?
Ecowas, the Economic Community of West African States, has mandated Senegal, which almost surrounds The Gambia, to spearhead military intervention, but only as a last resort and with the backing of the UN Security Council.
Wednesday was meant to be Mr Jammeh's last official day in office, but parliament extended his presidency by three more months. Still, Senegal set a deadline of midnight GMT for him to step down.
"If no political solution is found, we will step in," Col Abdou Ndiaye, a spokesman for the Senegalese military, was quoted as saying by Reuters news agency.
Nigeria has also sent aircraft and troops to Senegal, and deployed a warship.
Senegal has reportedly circulated a draft UN Security Council Resolution that would back Ecowas taking "all necessary measures" to get Mr Jammeh to step down.
What is the significance of the state of emergency?
Mr Jammeh's declaration of a state of emergency on his penultimate day in office has raised the stakes in his battle to remain in power.
The Gambian president said the state of emergency would prevent a power vacuum while the Supreme Court considered his legal challenge to December's election result. It cannot sit until at least May, due to a lack of judges, who must be provided by The Gambia's West African neighbours.
Analysts said the move, along with parliament's extension of his term, clearly signalled his rejection of mediation efforts.
Gambia is a popular tourist destination and after the British Foreign Office updated its travel advice, holiday companies have started evacuating tourists.
Where does this leave the election winner, Adama Barrow?
Mr Barrow, who is in neighbouring Senegal, said before the declaration of the state of emergency that his inauguration would go ahead on Thursday on Gambian territory.
The plan was for the swearing-in ceremony to take place at the National Stadium in Bakau but, given Mr Jammeh's latest moves, those plans must now be viewed as being in severe doubt.
There had also been no word on who would conduct the swearing-in - it is usually done by the country's chief justice but lawyers say that, under the Gambian constitution, this is not necessary and it could be carried out even by a commissioner of oaths.
How are the Gambian people reacting?
Tension is high in the Gambian capital, Banjul, over concerns that the political conflict will continue to escalate. Checkpoints across the city are being manned by heavily armed security forces.
Thousands of people have fled to neighbouring countries or rural areas, fearing that violence may erupt. Before the declaration of the state of emergency, Mr Barrow's coalition urged Gambians to "exercise restraint, observe the rule of law and not to respond to provocation".
The BBC's Umaru Fofana, who is in Banjul, says people there are petrified. They are stocking up on food and water. Everyone is praying for a peaceful resolution, he says.
What is Mr Jammeh's position?
Mr Jammeh, who seized power in a 1994 coup, initially accepted that Mr Barrow had won the election but later reversed his position and said he would not step down.
He filed a petition to the Supreme Court, challenging the election results, and says the existence of this legal process means it would be unconstitutional for Mr Barrow to assume office.
He also asked the Supreme Court for an injunction to stop the inauguration but the chief justice declined to rule on it, saying he must recuse himself from any case that could affect his own position - he would normally conduct the swearing in ceremony.
The secretary general of the Gambia Bar Association, Aziz Bensouda, said any such injunction would be unconstitutional.
Why is Mr Jammeh refusing to leave office?
Mr Jammeh has said there were irregularities in the election process, including the turning away of some of his supporters from polling stations, and errors made by the electoral commission.
The commission accepted that some of the results it initially published contained errors, but said Mr Barrow still won.
Mr Jammeh has said he will stay in office until new elections are held. Retaining power would also ensure he was not prosecuted in The Gambia for alleged abuses committed during his rule.
How have his allies reacted?
Ministers are continuing to desert Mr Jammeh's government. Four cabinet members, including the ministers of finance and foreign affairs, resigned on Tuesday. They join another two, who quit last week over the president's refusal to accept electoral defeat.
One of the ministers who resigned, former information chief Sheriff Bojang, said Mr Jammeh's arguments had a "veneer of constitutionalism" but were an attempt to subvert the will of the Gambian people. The international community has sided with Mr Barrow, saying he won fairly.
The Gambian army chief has declared his loyalty to Mr Jammeh.
The elite regiment of the army is also fiercely loyal, but other elements of the military may be less so.
Correspondents say there has been talk that some are unhappy with recent events and want a peaceful resolution.