Fighters attack ‘Africa’s Alcatraz’, which detains high-value prisoners, and disrupt crucial supply chains to the capital.

In a new wave of attacks in Mali, an al-Qaeda-linked group has stormed a main prison housing fighters from the armed group and set fire to trucks with food supplies heading to the capital Bamako.

Fighters from the Jama’at Nusrat al-Islam wal-Muslimin (JNIM) group stormed the Kenieroba Central Prison, a recently built complex dubbed “Africa’s Alcatraz”, located about 60km (37 miles) southwest of Bamako, Al Jazeera’s Nicolas Haque reported on Wednesday.

The detention centre houses 2,500 prisoners, including at least 72 inmates considered “high value” by the Malian state, Haque said, adding that Malian armed forces were repelling the attack.

Among the prisoners are JNIM fighters and a number of people arrested following large-scale attacks last month by the group’s fighters and Tuareg separatists, the Azawad Liberation Front (FLA).

The fighters attacked several military bases across multiple cities, including areas where senior government officials live, and took control of the northern city of Kidal in a coordinated offensive on April 25 and April 26, which struck at the heart of the West African country’s military government.

One of those attacks killed Malian Defence Minister Sadio Camara and his family in their home in Kati, a garrison town near the capital. On Monday, the leader of the country’s military government, Assimi Goita, took on the role of defence minister. At least 23 others were also killed in the attacks.

Since then, “there has been a wave of arrests of former and current military officers, members of civil society, lawyers, members of the political opposition – all accused of colluding with al-Qaeda fighters,” said Haque, who has been reporting for years on and in Mali. He added that fighters linked to the armed group were also arrested.

Security sources told AFP news agency that opposition figures Mountaga Tall, Youssouf Daba Diawara, and Moussa Djire are among those “abducted”.

According to family members and security sources who spoke to the agency, Tall, a lawyer, was taken on May 2 in Bamako by hooded men on charges of plotting with opposition figures in the Senegalese capital, Dakar, to overthrow the military government. Since his arrest, Tall has been questioned at least once for “attempted destabilisation”.

The security sources said Diawara and Djire were suspected of links with, respectively, the influential imam Mahmoud Dicko and Oumar Mariko, two opposition figures in exile. At least two other civilians who are close to Mariko were also arrested following the attacks, a judicial source told AFP, without giving further details.

The military prosecutor’s office said on May 1 that it had “solid evidence” of the “complicity” of certain military personnel, accusing them of helping with the “planning, coordination and execution” of the attacks.

In a report published on Tuesday, the Office of the United Nations High Commissioner for Human Rights (OHCHR) said there have also been “gravely concerning reports of extrajudicial killings and abductions, allegedly carried out by members of the security forces” following the attacks.

The violence has set off fighting across Mali’s vast desert north, raising the prospect of significant gains by armed groups that have shown an increasing willingness to strike neighbouring countries.

JNIM has called on Malians to rise up against the government and transition to Islamic law. The group has also pledged to besiege Bamako, and on Friday, it had reportedly set up checkpoints around the city of four million.

Haque said the blockade has the potential to cause a humanitarian disaster.

“These are al-Qaeda fighters that have pointed 12.7mm machine guns on their motorbikes, stopping any outgoing or incoming traffic,” the correspondent said. “We have seen on social media these fighters stopping food trucks trying to enter the area. This blockade is not just affecting people living in Bamako; it’s affecting people throughout Mali.”

On May 3, the mayor of Diafarabe village, in the Mopti region, called on the authorities to act before people started dying of hunger, as the village had run out of food.