Almost 30000 taxpayers submitted their returns via eFiling in the first nine hours of the 2015 Tax S.
"The disciplinary committee has already begun its process of notifying them that disciplinary steps are being taken against them," ANC provincial secretary Songezo Mjongile said.
He said the six, who were ANCYL members, would be disciplined under the ANC constitution. They face charges of bringing the party into disrepute, acting in a manner which was unbecoming and insulting Zuma.
Zuma was speaking at the Good Hope Centre, near the Cape Town CBD, on the night of February 23 when he was heckled. Fist-fights broke out and chairs were thrown. One of those injured in the ruckus was SABC cameraman Rudi le Roux, who had to have stitches to his left eye.
Two of the six people identified by the provincial party were facing criminal charges of public violence.
Sibusiso Nkomiyahlaba, 25, of Crossroads, and Siviwe Gxothiwe, 27, of Khayelitsha are out on bail of R500 and are expected to appear in the Cape Town Magistrate's Court on May 10.
The other four facing disciplinary action are Zuko Ngejane, Menzi Manyongo, Loyiso Nkohla and Mbi Nozulu Athenkosi.
Mjongile said the party had used video footage and photographs taken at the event to find the perpetrators.