DA leader Mmusi Maimane says the political party will not rest until there is justice for the families of Life Esidimeni victims.
"What took place [with] Life Esidimeni was a stain on the conscience of the South African government.
"None of us would have thought that such an act would have been committed in our democratic country," Maimane said on Thursday.
About 144 psychiatric patients died when the health department moved 1 700 people from Life Esidimeni to ill-equipped NGOs and state facilities. This occurred under the auspices of former Gauteng Health MEC Qedani Mahlangu.
Maimane's sentiments were shared at a Remember Esidimeni service outside Premier David Makhura's office in Mary Fitzgerald Square, Johannesburg.
WATCH: Angry Life Esidimeni victims' relatives tear down DA billboard
His comments came after there was outrage about a DA billboard ahead of the elections, which listed the names of several victims of tragedies in South Africa, including the one involving Life Esidimeni. Angry family members damaged the billboard, who said that the DA did not have their consent to use the names.
But Maimane apologised for the billboard and said the intention was never to hurt the families.
"I know that the decision opened up their wounds.
"I have spoken to these families and I want to say as a leader, that it was not our intention to hurt you and for that, I truly apologise," he said.
To date, 21 Life Esidimeni patients are still missing.
"One hundred and forty-four people have been recorded so far, but what is most painful is that we do not know the real number. The Gauteng provincial government must account.
"I want to assure Makhura and the ANC that you are not going to intimidate us. We will fight for these families."
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