Mali's security forces arrested more opposition leaders on Saturday and Prime Minister Boubuou Cisse said four people had died in major unrest in the vulnerable Sahel nation.
An almost insurrectional atmosphere pervaded the capital Bamako as authorities cracked down on the opposition alliance known as the June 5 Movement, even as Cisse promised a government "open to facing the challenges of the day".
A total of six opposition figures have been detained in two days as the movement vowed to turn up the heat until embattled President Ibrahim Boubacar Keita quits.
As Cisse visited a hospital in the capital he spoke of four dead and around 50 people injured in clashes with security forces on Friday, but doubts were raised over the death toll from some of the worst unrest in years.
Friday saw widespread protests against Keita, with thousands rallying in Bamako to demand his resignation over a long-running jihadist conflict, economic woes and perceived government corruption.
Deep-seated frustrations
On Saturday, Cisse told media: "The president and I remain open to dialogue," and added that he would quickly form a government ready to deal with the country's problems.
But almost as he spoke, Malian gendarmes arrested Choguel Maiga and Mountaga Tall, both leaders in the June 5 Movement, a group spokesman said.
Later Saturday, security forces turned up at the house of another opposition leader, Sy Kadiatou Sow, but were unable to find him, said a member of his family who did not want to be named.
Led by influential imam Mahmoud Dicko, the movement is channelling deep-seated frustrations in the West African country.
Two other opposition leaders, Issa Kaou Djim and Clement Dembele, were arrested late Friday, the alliance said, and two figures considered intellectual pillars of the movement were also detained, it added.
Friday's protest was the third such demonstration in less than two months -- significantly escalating pressure on the 75-year-old president.
'Step up' pressure
Keita warned Saturday that security would be maintained "with no signs of weakness", while indicating his willingness "to do everything possible to calm the situation".
The alliance called on the public "to maintain and step up this mobilisation until the aim is achieved, which is the resignation of the president".
The opposition's call for civil disobedience includes the non-payment of fines and blocking entry to state buildings.
Security forces broke into an opposition meeting that was examining ways to pursue a campaign of civil disobedience and obtain the release of those who had been arrested, spokesman Kaou Abdramane Diallo said.
Security officials "were looking for armed men, and came in cars and rammed the gate", an opposition member said on condition of anonymity.
On Friday, demonstrators had attacked parliament and ransacked the national television station, only dispersing when the security forces opened fire.
The day after, officials were counting the cost of the violence.
That included six vehicles burnt, others with windscreens smashed, a scanner stolen and other equipment damaged, the head of the state-run television and radio network, Salif Sanogo, told AFP.
Security forces were guarding the station as it resumed broadcasts on Saturday.
This level of violence is rare in Bamako, which has been spared much of the violence that is routine across swathes of Mali.
The country has struggled to contain an Islamist insurgency that first emerged in the north in 2012, before spreading to the centre of the country and to neighbouring Burkina Faso and Niger.
Thousands of soldiers and civilians have been killed and hundreds of thousands of people have been forced from their homes.
By Saturday evening, groups of men had set up road blocks at major junctions, burning tyres and throwing stones at members of the security forces.
After weeks of growing political tension, Keita offered Wednesday to appoint new judges to the constitutional court.
It has been at the centre of controversy since April 29, when it overturned provisional results for March's parliamentary poll for about 30 seats.
That saw several members of Keita's party elected and triggered protests in several cities and is widely seen as having ignited the country's latest crisis.