Burundi President Pierre Nkurunziza arrives at the White House during the US Africa Leaders Summit on August 5, 2014 in Washington, DC
Bujumbura (Burundi) (AFP) - With a president who won't go and an opposition determined to blow the final whistle, battle lines are being drawn ahead of elections in the central African nation of Burundi.
Determined to stay put despite a two-term constitutional limit, President Pierre Nkurunziza stands accused of trying to sideline political challengers ahead of the June vote, with measures including arrests, harassment and a clampdown on free speech.
But with the opposition and civil society groups mobilising, disapproval from the influential Catholic Church and even a split within the ruling party, there are worries the landlocked country is on the brink.
On top of that, Burundi is still recovering from a brutal 13-year-long civil war that ended in 2006 and is part of a region beset by genocide and rebellion.
"It's the first time in Burundi's history that there has been such a polarisation" of national politics, said Julien Nimubona, professor of political science at the University of Burundi. He said both camps appear to see violence as a solution.
"There will be more of a cost for him and the country if he stands than if he doesn't," the professor warned.
Recent months have seen the crisis over Nkurunziza's expected candidacy worsen.
In mid-February, the lakeside capital of Bujumbura, where grinding poverty is the norm for many, was gridlocked by a huge demonstration in support of a popular government critic and journalist who was arrested after implicating government agents in a murder case.
The march served to galvanise calls in Burundi to "stop a third term", a campaign that has since been joined by the Catholic Church -- which declared it had concluded the president had to go after two terms.
But Nkurunziza, a former Hutu rebel leader and born-again Christian, is fighting back. He sacked his powerful intelligence chief and two deputies after sources said the general wrote to the president asking him not to run again.
According to several stop state officials, the question has prompted a "real uneasiness" and even "a crisis" within the ruling CNDD-FDD party, as no other clear successor is in view. At the same time, the opposition says it will not repeat its 2010 boycott of the polls, and analysts say they have every chance of causing an upset.
"We are in a context where the internal revolt is intensifying," a Bujumbura-based diplomat said, commenting on tensions with both the CNDD-FDD and the powerful armed forces.
- 'Mood for a riot' -
Burundi's constitution allows a president to be elected to two five-year terms, but Nkurunziza argues he was only once directly picked by the people -- as Burundi's parliament chose him for his first term, beginning in 2005.
It is now up to his party to choose him as their candidate and for the constitutional court to validate it. On this, Interior Minister Edouard Nduwimana has appealed for "patience".
Although Nkurunziza, a football-mad father-of-five, is the latest in a long line of African leaders who have tried to stay put, his opponents may be encouraged that the tide is turning.
In one example, Burkina Faso's former president Blaise Compaore was chased out last year after he tried to bend the rules in his favour.
Key donors are also critical: speaking last week during a UN Security Council visit to the country, US ambassador Samantha Power described Nkurunziza's ambitions as "extremely divisive" and "very destabilising".
Implicitly telling him to bow out gracefully, she called on Burundi's leaders "to make decisions on the basis of what is good for the people of Burundi and for peace."
On the streets of the capital, the tension is palpable -- with anger brewing over alleged repression but also inflation, corruption and poverty.
Hidden from view but not from conversation are the Imbonerakure, the CNDD-FDD's youth wing who rights activists allege have been secretly armed and trained in neighbouring Democratic Republic of Congo -- reviving among some observers bad memories of the lead-up to the 1994 genocide in neighbouring Rwanda.
"Certain people seem to be drawn into a logic that the worst will happen," said Thierry Vircoulon of the International Crisis Group, a conflict-prevention think-tank, suggesting the CNDD-FDD could steer the country off its current drift to violence by choosing an alternative candidate.
"There is an increase of electoral tensions in both camps, and the mood for a riot in Bujumbura."