A man who was arrested earlier in the day over the parliament blaze is due to appear in court on Tuesday, media reported, citing police.
Earlier, South African President Cyril Ramaphosa said that someone was being held for questioning in connection with a massive fire that erupted at the parliamentary precinct in the early hours of Sunday morning.
"I believe somebody is being held right now and they are being questioned," Ramaphosa told reporters as aired by South African SABC News broadcaster.
The parliament of the republic said that as the result of the fire, no one was injured.
"No person has been injured. The Presiding Officers of Parliament are distressed by this incident and the extent of the damage caused thus far to the precincts of the seat of the national legislature. They have urged all relevant authorities to leave o stone unturned in establishing the cause of fire," the parliament tweeted.
According to the parliament, the blaze affected the National and the Old Assembly buildings.
The Cape Town Parliament complex consists of several buildings — an old building dating back to the 19th century and new ones from the 1920s and 1980s that are used by the lower house.
In April, a major fire started near Cape Town, which engulfed the campus and the Cape Town University library. The fire was localized only on the fourth day.