Burundi’s army chief of staff has survived an assassination attempt on a busy road in the capital, Bujumbura.

General Prime Niyongabo was heading to his office in the morning when armed men attacked his motorcade.

Burundi’s deputy police chief Gen Godefroid Bizimana told the AFP news agency the army chief was unharmed.

Burundi has suffered serious unrest since April, when President Pierre Nkurunziza said he would seek a third term in elections he later won.

In May he survived a coup attempt.

A senior army general and close aide to the president, Adolphe Nshimirimana, was killed last month in similar circumstances.

Earlier this week the spokesman for a party opposed to President Nkurunziza’s third term was shot dead in Bujumbura.

The BBC’s Prime Ndikumagenge in Bujumbura says the men who attacked the motorcade on one of the busiest roads in the south of the city were armed with guns and rockets.

A military source told the BBC that three bodyguards and one of the attackers were killed during the attack.

Four of the gunmen had been captured, two of whom were wounded, the source said.

A senior police source told AFP the attackers were wearing military uniforms and travelling in a military vehicle.

“He [the army chief] managed to survive only because the driver managed to overtake a bus transporting police officers to work, and the attackers could not keep up,” the police source said.

Our correspondent says images circulating on social media show three people at the scene in military uniform who are either dead or wounded but it is difficult to establish if they were the attackers or part of the motorcade.

At least 100 people have died in protests, mainly in Bujumbura, since Mr Nkurunziza announced his decision seek another term in office.

The government accuses the opposition, which says the third term is illegal, of causing the violence.

The political tensions there have forced tens of thousands people to flee the country this year.