Pretoria - Dr Vejay Ramlakan arrived on Wednesday at the Medi-Clinic Heart Hospital in Pretoria, where former president Nelson Mandela remains in a critical condition.
Ramlakan is the country's former surgeon general. He stepped down earlier this year.
His car was not searched by the police and security guards when he arrived at the hospital.
Security at the private hospital has been increased since Mandela was admitted on 8 June with a recurring lung infection.
Police started searching vehicles entering the facility at about 05:00.
Earlier, Tshwane metro police officers barricaded part of Celliers Street, leading to the hospital's main entrance.
Numerous traffic patrol cars were also in the area.
Burning candles, bouquets of pink and red flowers, paintings, and hundreds of messages adorned the wall at the main entrance.
Well-wishers transformed the wall outside the hospital into a miniature art gallery with presents, get-well cards, balloons and floral tributes in support of Mandela.
The presidency said on Tuesday that the anti-apartheid icon remained in a critical condition.
"[Mandela's] condition remains unchanged in hospital, and doctors continue to do their best to ensure his recovery, well-being, and comfort," spokesperson Mac Maharaj said in a statement.