Chris Botha said the injured woman was airlifted to the Chris Hani Baragwanath Hospital in Johannesburg.
"It was the only ICU bed available," he said. "She is in a very, very critical condition."
He did not want to comment on whether this had anything to do with the public service strike.
The accident happened near the Ruth First offramp on the R80 in Pretoria at 07:30 on Monday morning.
Botha said the minibus taxi she was travelling in collided with a truck. The cause of the accident was not known.
"The taxi was ripped open on the passenger side where the female was seated, causing extensive injuries to the patient," said Botha.
Botha said the woman was still unconscious and on a ventilator, and it would be "very difficult" to say if she would survive.
Police could not immediately be reached for comment.
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