Relatives of the Life Esidimeni victims claimed responsibility for damaging and tearing down the DA's newly unveiled "The ANC is Killing us" billboard in Braamfontein, Johannesburg, on Thursday.
Soon after the billboard was damaged, the DA responded by calling the act "criminal".
READ: ANC, DA welcome expanded SIU probe into Life Esidimeni
Video footage was circulated on WhatsApp on Thursday of two men cutting and tearing at the billboard, unveiled on Wednesday, which lists the names of people who died in the Marikana massacre, the Life Esidimeni victims and children who died in pit toilets.
"It's quite clear that this is a criminal act," DA spokesperson Solly Malatsi told News24.
"It appears that the ANC and/or its sympathisers are shaken by [the billboard]."
Malatsi said this was not the first time DA billboards had been defaced.
'We are still mourning'
"A few years ago we had a billboard on jobs lost under the ANC and that was also damaged.
"We will be engaging with the relevant authorities for the law to take its course," Malatsi said.
Malatsi firmly believes ANC supporters or sympathisers are behind the vandalism.
"We cannot detach the ANC from this given the strong words they have expressed against the billboard."
However, News24 spoke to a family member of one of the Life Esidimeni victims who claimed that the damage was done by relatives of those victims.
"We are still mourning for them, we will never speak to them again, and now their names are out there," the man, who did not want to be named told News24.
"What's done is done."
The relative said none of the family members were consulted by the DA prior to having the billboard erected.
"This is what angers us," he said.
DA will report matter to police
At least 144 people died when psychiatric patients were moved to unregistered facilities by the Gauteng health department.
Malatsi would not disclose what the billboard cost or what the cost of repairs could be. Because the incident took place less than an hour before News24 spoke to Malatsi, he could not say whether or when the DA would repair the damage.
"We will allow the law to run its course. The priority is that those who are responsible be arrested. Then we will determine the next step regarding the future of the billboard."
Malatsi said the party would be engaging with the police as soon as possible.
Johannesburg Mayor Herman Mashaba tweeted: "Is there anything that the ANC does not want society to know?"
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