An IT expert has been charged with hacking into Kenya’s Revenue Authority and stealing $39m (£31m).
Alex Mutunga Mutuku, 28, is accused of electronic fraud but he denies any wrongdoing.
The prosecution says he is part of a wider network that is stealing money from several high-profile institutions.
Mr Mutuku was arrested after police conducted an operation following a tip-off that institutions were losing money.
A lawyer for Mr Mutuku, Tacey Makori, has asked for him to be released, arguing that police had failed to show enough evidence to warrant an extended detention.
He is being held while anti-cybercrime officers dig deeper into what they believe is an elaborate fraud scheme with international connections.
It allegedly involves hackers with access to high-tech equipment and software which enabled them to steal from corporations, Kenya’s Standard newspaper reports.
“It is a case of remote control hacking where the suspects operate smoothly with their machines and the next minute you realise you have no money in your account,” state prosecutor Edwin Okello is quoted by the newspaper as saying.
“The information we have is just a tip of the iceberg. The racket is big and involves people outside the country.”
Earlier this week, Kenyan police said a Chinese company was behind a spate of criminal activities, including the hacking of Kenya Revenue Authority.