Before he got into power in May, Mr Buhari vowed to investigate corruption in the previous government, in which Mr Dasuki served. The BBC's Bashir Sa'ad Abdullahi says soldiers have reported they are better equipped since President Buhari came into office, but the previous president's supporters say this is because those weapons were ordered while Goodluck Jonathan was in power. A spokesman for Mr Buhari said the corruption resulted in the needless deaths of thousands of Nigerians. Boko Haram has killed thousands in north-eastern Nigeria in its campaign to create an Islamic state. In the latest militant attack, at least 32 people were killed by a suicide bomber on a vegetable market in the north-eastern city of Yola on Tuesday night. This led Facebook to activate its safety check feature for the first time following an attack in Nigeria.