Fighters linked to al-Qaeda have seized a military base in central Mali and set up armed checkpoints on roads leading into the capital, Bamako, in what amounts to the most serious challenge to the country’s military government since it took power through back-to-back coups in 2020 and 2021.

Some military officers in Mali worked with jihadis and separatists who recently launched their biggest round of attacks in over a decade in the conflict-battered country, authorities said late Friday.