"We need a professional police service to catch violent criminals, not a trigger-happy police force that kills innocent civilians," DA police spokesperson Dianne Kohler-Barnard in a statement.
On Tuesday, Mido Macia (27) a taxi driver from Mozambique, was tied to the back of a police van and dragged along a street in Daveyton, on the East Rand. An eyewitness filmed the assault.
Macia died in the local police station's cells later that day.
A post mortem revealed that he had died of head and internal injuries.
Eight policemen have been arrested and were expected to appear in court on Monday on a murder charge.
Kohler-Barnard said Macia's death came too soon after the Marikana shootings in August, in which 34 striking mineworkers were shot dead and 78 were injured when the police opened fire, allegedly while trying to disperse a group of workers gathered on a hill.
"It's not enough to merely ask questions about specific incidents such as Marikana and Daveyton," she said.
"This country needs to know there is a plan to ensure they are not repeated over and over again."
Kohler-Barnard said the establishment of a commission of inquiry into police brutality was, therefore, a matter of urgency.
Mokonyane visits Macia family
The Gauteng government on Thursday said it would help Macia's son.
"We learned that he had only one dependent in SA, his seven-year-old son. We will take care of him for the duration of this year until we are guided by the family on whether he goes back to Mozambique or not," premier Nomvula Mokonyane's spokesperson Thebe Mohatle said.
Mokonyane visited Macia's family in Daveyton, on the East Rand, on Friday. She sent her condolences to the family and condemned the police's actions. Mohatle said the provincial government would work with the South African embassy in Mozambique to help the family with arrangements for taking Macia's body home.
'Barbaric'
The National Council of Trade Unions (Nactu) on Friday described the incident as "barbaric".
"For police to tie another human being to [a] police vehicle and in full view of the onlookers, drag the person to his death is [an] act of barbarism that defies logic," Nactu general secretary Narious Moloto said in a statement.
"[T]he South African Police Service harbours within its ranks police with criminal tendencies … [of] which communities should be concerned."
Moloto said a probe should be conducted to determine whether the country's police officers were fit to do their jobs.
He called on Police Minister Nathi Mthethwa to take responsibility for the officers' conduct.
"If I were Nathi Mthethwa I [would] hang my head in shame, and even consider resignation."
Moloto said police officers operated in the same manner as their apartheid-era counterparts.
"When former police commissioner Bheki Cele instructed his police to shoot to kill, the presidency and the police ministry looked the other way, and failed to call Cele to order, reminding him that South Africa is a constitutional democracy, and that the provisions of the Bill of Rights of the Constitution protect all the citizens from having their life threatened by gun-toting police," he said. – Sapa