The Luanda Leaks investigation is a landmark moment for Angola (Revealed: how ‘princess’ of Angola built $2bn fortune, 20 January). It should be a landmark moment for the world. The revelations should inform the criminal investigation into Isabel dos Santos that is already under way. This investigation must follow due process (Angola vows to force Dos Santos to return, 21 January).

It ought to be remembered that João Lourenço’s anti-corruption drive has not been undertaken in an even-handed manner. If the president is to truly deserve the tag of “The Terminator” of corruption, he can no longer ignore allegations of graft against those close to him.

Moreover, PwC, Accenture and other professional services firms implicated in reports by the Guardian and the International Consortium of Investigative Journalists must hold transparent investigations and cooperate with law enforcement (Heads could roll at PwC over firm’s link to the richest woman in Africa, 22 January). Regulatory bodies should hold these firms to account.

Ultimately, they must be subject to stronger legal requirements to screen their clients on an ongoing basis and to report suspicious activity to law enforcement. And there is a need for the UK and other governments to crack down on the tax havens that are used to facilitate corrupt deals.

Sunit Bagree

Action for Southern Africa

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