Burundi's constitutional court says it has approved President Pierre Nkurunziza's bid for a third term.

The statement came on Tuesday as dozens of protesters marched in the capital Bujumbura to say they would "never accept" a campaign they call illegal.

Police also fired tear gas at protesters as they approached the US embassy.

 Al Jazeera's Malcolm Webb reports from Bujumbura

Nkurunziza's announcement that he would stand in a June 26 vote has plunged Burundi into its worst political crisis since its ethnically fuelled civil war ended a decade ago.

"The renewal of the presidential term through direct universal suffrage for five years is not against the constitution of Burundi," a constitutional court statement said.

Agathon Rwasa, a leading opposition, told Al Jazeera that the ruling was a "coup".

"Their decision is nothing but a coup against the Arusha accord, and the current constitution," Rwasa told Al Jazeera, referring to a peace agreement that ended ethnic conflict in nearby Rwanda.

"It is a clear message to the people that they count for nothing, and that only Nkurunziza and his friends count in this nation."

Al Jazeera's Malcolm Webb, reporting from Bujumbura, said that people do not accept the ruling, as at least four of the seven constitution court judges had fled the country.

"We don't care about the constitutional court decision because we know this court is manipulated," Jean Minani, leader of Frodebu-Nyakuri party, part of one coalition behind the protests, told AFP news agency. He said rallies would not stop until the president backed down.

Judge Sylvere Nimpagaritse, the constitutional court's vice president, fled to Rwanda on Monday.


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Nimpagaritse told AFP news agency that the court's judges had come under "enormous pressure and even death threats" from senior figures, which he refused to name, to approve the disputed candidature of the Nkurunziza.

He said that a majority of the court's seven judges believed it would be unconstitutional for Nkurunziza to stand again.

Following the court's ruling Vice President Prosper Bazombanza offered an olive branch, promising to release hundreds of protesters and reopen radio stations if the demonstrations stop.


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"To create a climate of appeasement, the government is willing to release the young people who were arrested," Bazombanza said.

He also offered to lift arrest warrants issued against key civil society leaders and reopen independent radio stations, provided that "protests and the insurrection stop".

Calls for peace

Meanwhile, civil society groups say at least 12 people have been killed so far in clashes in which police have fired tear gas, and water cannon.

Police, who put the toll at six, including three members of the security forces, say protesters have hurled grenades.

Rwanda's Foreign Minister Louise Mushikiwabo said she was concerned about the unrest, which shares the same ethnic mix as Rwanda where a 1994 genocide killed 800,000 people.

"While we respect Burundi's sovereignty in addressing internal matters, Rwanda considers the safety of innocent population as a regional and international responsibility," she said in a statement, urging the government to restore peace.

At least 24,000 people have fled to Rwanda in recent weeks as tensions have mounted. About 7,000 people have also crossed into neighbouring Democratic Republic of Congo.

Protesters hold placards as they demonstrate against the ruling CNDD-FDD party's decision to allow Nkurunziza to run for a third term [File: Reuters]

Source: Al Jazeera and agencies