Nigeria’s former national security adviser, Sambo Dasuki, has been arrested for allegedly stealing $2bn (£1.3bn), his representatives say.
Mr Dasuki is accused of awarding phantom contracts to buy 12 helicopters, four fighter jets and ammunition. He denies the allegations.
The equipment was meant for the fight against Boko Haram Islamist militants.
Mr Dasuki was picked up early in the morning by security agents, a PR firm representing him said.