In 2016, Buhari was reportedly presented evidence that his chief of staff, Abba Kyari, took N500 million naira bribe from MTN to help it slash the $5 Billion dollar fine slammed against it for violation of Nigeria telecommunications regulations bothering on national security. MTN fired the staff involved in the bribery scandal. But Abba Kyari was left intact in his position as chief of staff to national outrage forcing Buhari to announce the probe of Kyari. The findings of the investigation was never made public.