51-year-old Sir Mark, who denied any knowledge of the plot, admitted in a Cape Town court to breaking anti-mercenary legislation in South Africa by agreeing to charter a helicopter, which mercenaries planned to use in their attemped takeover.
But, Sir Mark, who agreed a plea bargain with prosecutors, maintained that he did not know the helicopter's alleged purpose, and thought it was to be used as an air ambulance, according to his lawyers.
"There is no price too high for me to pay to be reunited with my family and I am sure all of you who are husbands and fathers would agree with that," an emotional Sir Mark said outside the court.
Cape High Court Judge Abdullah Motala ordered Sir Mark,a businessman, to pay the USD 505,000 fine in a deal that lets him leave South Africa to be reunited with his wife and two children in the US.
If he is unable to pay the fine by the deadline of January 15, he would incur a five-year prison sentence, with his four-year suspended sentence on top of that.
However, Sir Mark promised to pay the fine by the deadline. Sir Mark, who has lived in South Africa since 1995, was arrested on August 25 and released on bail. He was charged with violating anti-mercenary laws and barred from leaving the country pending investigations.
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