The disturbances started last week in the capital Ouagadougou and have spread An army mutiny which erupted last week in the West African state of Burkina Faso has spread to a fourth city.
Protests have now broken out in Kaya in the north of the country, following disturbances in Po and Tenkodogo.
The trouble started last Thursday when soldiers and presidential guards in the capital Ouagadougou protested about unpaid housing allowances.
Hours before the revolt broke out, tens of thousands of people had demonstrated against high food prices.
'Police join mutiny' President Blaise Compaore, a former coup leader in power since 1987, has sacked his government and appointed a new head of the armed forces to try to quell the unrest.
His government warned on Sunday that mutinous soldiers would face "the full force of the law".
BBC Ouagadougou correspondent Mathieu Bonkongou confirmed that the unrest had now reached Kaya.
Soldiers and police reportedly took to the city's streets late on Sunday and began firing guns into the air until the early hours of Monday.
It is said to be the first time that police have taken part in the mutiny.
The violence in the capital had seen at least 45 injured people admitted to hospital.
In March, some soldiers went on the rampage and managed to free a number of colleagues arrested for rape.