Computers and hard drives stolen from the Hawks' national headquarters in Pretoria contained sensitive information about anti-corruption investigations involving the directorate's disgraced former head, Berning Ntlemeza.

The Times has learned that the hardware stolen on Tuesday night stored information about what is thought to have been the irregular appointment of numerous people to senior and administrative positions in the crime-fighting unit.

The appointments were apparently made by Ntlemeza, who is fighting his dismissal by Police Minister Fikile Mbalula in the Supreme Court of Appeal, in Bloemfontein.

Hawks spokesman Brigadier Hangwani Mulaudzi confirmed that an internal investigation into appointments within the organisation was under way.

"[The investigation] was ordered by acting Hawks boss Lieutenant-General Yolisa Matakata."