Gauteng Hawks head Maj-Gen Shadrack Sibiya was served with a notice of suspension on Monday, the Hawks said.

"He has been served with a notice of suspension but has not been suspended yet," spokesperson Captain Paul Ramaloko said.

"The notice will run for seven days and Maj-Gen Sibiya has welcomed every action and wants this process to be completed to clear his name."

Ramaloko said the notice of suspension came after an investigation that was already underway. He could not immediately provide a reason for the notice of suspension.

Sibiya had seven days to indicate why he should not be suspended.

Sibiya is not the only senior Hawks officer facing suspension.

On December 23, Hawks boss Anwa Dramat was suspended, apparently pending a probe into his alleged involvement in facilitating the illegal rendition of Zimbabweans in November 2010.

On December 30, the police dismissed reports that Dramat was asked to provide information about the Nkandla investigation to police commissioner Riah Phiyega.

At the time, Ramaloko said the National Investigation Unit, under Lt-Gen Vinesh Moonoo, was looking into the R246-million spent on upgrades to President Jacob Zuma's private homestead in Nkandla, KwaZulu-Natal.

Democratic Alliance MP Dianne Kohler Barnard said her party believed Dramat's suspension – ordered by Police Minister Nkosinathi Nhleko on December 23 – was linked to Nkandla.

However, Ramaloko dismissed these claims.

Earlier, during an interview with Radio 702, Dramat's advocate Johan Nortje mentioned Nkandla as a possible reason behind the suspension.

Nortje said the reason given in a letter by Nhleko and Phiyega for Dramat's suspension – that he was facing allegations into illegal rendition of Zimbabweans in 2010 – was "baseless".

He said a report into the matter had cleared Dramat months ago.

Nortje said that according to a recent court ruling the suspension was unconstitutional.

The ruling was part of a larger judgment dealing with the constitutionality of legislation to establish the Hawks.

The court found certain defects in the laws – such as the "untrammelled" power given to the police minister to dismiss the head of the hawks – had to be "severed".

Dramat's lawyers have given Nhleko until January 5 to lift the suspension.

On December 26, KwaZulu-Natal Hawks boss Johan Booysen confirmed he was not suspended.

He referred Sapa to a recent court interdict that prevented him from "inter alia being transferred, suspended or dismissed".

On December 18, Judge Peter Olson of the Durban High Court granted the urgent interdict that prevented the police from discharging Booysen or shifting him to another province.

At the time, the Helen Suzman Foundation said it was troubled by the suspension of both Dramat and "his KwaZulu-Natal counterpart".

However, Booysen had subsequently clarified the remark was inaccurate.

Various reports suggested police officials had been trying to get rid of Booysen since August 2012, when he was charged with racketeering for allegedly receiving payment to carry out hits in the KwaZulu-Natal minibus taxi wars.

In March this year, all criminal charges against him were withdrawn.

However, police still pursued disciplinary charges against him linked to his alleged failure to act against members of the Cato Manor serious and violent crimes unit for their alleged excessive use of force.