"The matter is viewed by the national commissioner in a very serious light and it is strongly condemned,” said her spokesman Brigadier Phuti Setati.
Mozambican Mido Macia, 27, was found dead in the holding cells of the Daveyton police station, in Benoni, on Tuesday night, allegedly after being dragged behind a police vehicle. Setati said the death had been reported to the Independent Police Investigative Directorate (Ipid) for criminal investigation and the police would fully co-operate with its investigation to ensure justice was served.
Phiyega had also instructed acting provincial commissioner Maj-Gen Phumzo Gela to immediately start an internal investigation into the death and to provide feedback as a matter of urgency, he said.
Amnesty International called the death shocking.
"This appalling incident involving excessive force is the latest in an increasingly disturbing pattern of brutal police conduct in South Africa,” Amnesty International’s Southern Africa director Noel Kututwa said in a statement.
"Amnesty International urges the South African government to make a public commitment to ensure that the police stop the use of excessive force and deliberate targeted killings.” The SA Human Rights Commission said it supported and welcomed the Ipid investigation.
"We urge the Ipid to move with necessary speed and accuracy to establish the cause of this man’s death and to ensure that those responsible are brought to book,” spokesman Isaac Mangena said in a statement.
He said the death or assault of anyone in police custody was a matter of concern which deserved full investigation. "Police brutality cannot be tolerated under any circumstances.” On Wednesday, Ipid confirmed that the death was being probed.
"We are still interviewing the witnesses because the allegations are that he was dragged [along] with the police vehicle,” said spokesman Moses Dlamini.
He said two policemen switched on their siren, indicating that Macia should move his vehicle, when they saw it obstructing traffic in Empilweni Street on Tuesday.
"It is also alleged that the taxi driver then assaulted the constable and took his police firearm,” he said.
"The warrant officer overpowered the taxi driver and handed the firearm back to his colleague,” he said.
The warrant officer then took a taxi to the Daveyton police station to call for back-up.
"When back-up arrived, the constable was still at the scene, struggling to put the suspect in the police van,” said Dlamini.
He said officers put the "resisting suspect” into the police van and took him to the police cells.
He was found dead by another police officer later in the day.
An inquest docket had been opened, and the police had also opened a case of assault with intent to cause grievous bodily harm against the man.
Dlamini said a post mortem conducted on Wednesday indicated that the man died of head injuries, with internal bleeding.
"They [policemen] are only saying they locked him [up] and he was found by another police officer, but we are investigating,” he said. - Sapa