Twin brothers Brandon-Lee and Tony-Lee Thulsie are facing terrorism-related charges. Picture: Facebook

Johannesburg - Twins Brandon-Lee and Tony-Lee Thulsie, who are accused of terrorism, are expected to appear in the Johannesburg High Court on Friday for a pre-trial conference.

The Thulsie twins were arrested in July 2016, and have been charged with 12 counts relating to contraventions of the Protection of the Constitutional Democracy Against Terrorist and Related Activities Act and the 13th charge is for fraud, linked to the alleged use of fake passports.

They were allegedly plotting a series of attacks on behalf of the Islamic State terrorist group against Jewish targets and the embassy of the United States of America (USA).

On October 20, Attorney Annelene van den Heever, for the Thulsies, told the court that she intended to challenge the constitutionality of the South African Terrorism Act.

In pretrial proceedings, Van den Heever told Judge Raylene Keightley that she would be submitting a constitutional defence application and that she would make other pretrial applications. Keightley ordered Van den Heever to prepare a pretrial draft with time lines.

The twins have been behind bars since their arrest in July 2016. A 13-page indictment of the matter suggests that the twins were attempting to join militant Islamist group Islamic State of Iraq and the Levant (ISIL, also known as ISIS) and that the terrorist activities would have been perpetrated by using firearms, explosives and possibly poisons. 

The attacks would have been directed at various embassies of countries including the United Kingdom, Russia, and USA based in Pretoria. Other targets listed included cartoonist Jonathan Shapiro (known as Zapiro), Jewish South African Investment Manager, Roy Topol, and King David High School Linksfield.

In September, the USA froze their assets, as well as imposing other sanctions on the brothers.