The 25-year-old student arrested for "waving" at President Jacob Zuma's convoy last week swore at the president and resisted arrest, a spokesman has said.
Police Ministry spokesman Zweli Mnisi said Chumani Maxwele had pointed his middle finger at the president. He said this gesture was synonymous with swearing and showing disrespect.
"No person is permitted to use foul language, swear at another individual, especially as such conduct may lead to promoting hate conduct in the Republic," said Mnisi.
The Sowetan reported on Tuesday that Maxwele had been arrested for "waving on" Zuma's convoy while jogging in De Waal Drive, Cape Town.
A black BMW pulled up and three men jumped out, allegedly pointing guns at him. He was then pushed into a car. A bag was pulled over his head and he was then allegedly taken to Zuma's residence before being taken to the Mowbray police station.
Maxwele, an active ANC member, was held for just under 24 hours. He was allegedly interrogated by intelligence agents who asked for, among other things, the names of his friends and the name of the chairmen of his ANC branch.
He said his house had been raided by plainclothes policemen while he was in custody. He was released before appearing in court.
Mnisi said Maxwele had become aggressive on the day of the incident when the police stopped to question him about his actions.
"He became aggressive and began to swear at them. They then arrested him, charged him with crimen injuria and resisting arrest," said Mnisi.
"He was detained and later transferred to Mowbray Police Station, which has jurisdiction over the area of offence."
Mnisi called Maxwele's conduct towards the police "unacceptable".
"It will not be tolerated," he said.
Mnisi declined to comment about allegations that agents of the National Intelligence Agency had raided Maxwele's house or interrogated him.
"We further need to clarify that the matter was handled solely by the police, as it forms part of our mandate of protecting all VIPs," said Mnisi.
He did not answer a question about whether Zuma himself had pressed charges against Mxwele.
Zizi Kodwa, the president's spokesman, declined to comment, claiming it was a "security issue". - Sapa