Known as Maj. Hamza Mustapha, the former security chief of the late Nigerian dictator Sani Abacha, is charged with financing efforts to buy "a Stinger surface-to-air missile to be used in shooting down the president's helicopter with the president on board," the BBC reported Friday.
The plot was discovered in April, officials said.
Mustapha has been in prison since 1999 when he was accused of the attempted murder of a newspaper publisher who criticized the Abacha regime.
Besides Mustapha, two other military officers and a businessman have been charged in the alleged plot.
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