More high-profile visitors have arrived at Milpark Hospital in Johannesburg where former president Nelson Mandela is being treated.
Anti-apartheid activist Albertina Sisulu entered the hospital in a wheelchair, followed by Mandela's eldest grandson, chief Mandla Mandela and his younger brother.
Justice minister Jeff Radebe, Mandela's former wife Winnie Madikizela-Mandela, his personal assistant Zelda la Grange and the daughter of Mandela's wife Graca Machel arrived earlier.
Senior military officials were seen entering hospital grounds on Thursday afternoon.
A number of police vehicles entered the premises and officers with sniffer dogs began to scour the area around a temporary barricade of dark green shade netting and potplants set up to hide the rear entrance.
International and local journalists were barred from entering the hospital premises and could only get a clear view of the area by parking on a nearby bridge, overlooking the hospital.
A journalist from a Chinese news agency who managed to sneak past security and get into the hospital had his camera confiscated by police.
One of Mandela's bodyguards came out and asked police to “clear this space for us for when we come out”.
There has been no word on the 92-year-old statesman's condition. The hospital was not planning to comment.
Mandela was admitted there on Wednesday for what the Nelson Mandela Foundation called “routine tests”.
The hospital public relations officer was seen taking refreshments and newspapers into the wing where Mandela was being treated.
The ANC Youth League sent its best wishes.
“Nelson Mandela remains our greatest inspiration in everything we do and we confident that he will stay strong.
“The Message from the ANC Youth League is best wishes Tat’u Madiba, the Youth of the ANC, South Africa and the entire world Love you President Nelson Mandela,” a league statement read.
The Star newspaper reported on Thursday that Mandela was seen by Professor Michael Plit, a specialist pulmonologist (who deals with diseases of the respiratory system).
“He has been admitted for investigation,” Plit was quoted as saying.
He would not say what Mandela's condition was or if he had examined him, except to say he had seen him on Wednesday.
The newspaper described him as Mandela's personal physician.
On the National Asthma Education Programme website, Plit describes his medical interests as obstructive lung diseases, such as asthma and chronic obstructive pulmonary disease.
ANC spokesman Jackson Mthembu issued a statement calling for the media to stop speculating about Mandela's health and allow the family privacy.
“We appeal, particularly to the media fraternity, to refrain from making unfounded and unwarranted speculation in relation to Madiba's health,” he said.
“In the same vein we also request the media, in particular, to give Madiba's family and the hospital the necessary privacy.”
He said South Africans would be informed of any change, including if Mandela were to be discharged from hospital.
Beeld newspaper reported that it appeared Mandela was in the hospital's private unit for burn victims.
The unit's windows were covered to ensure privacy and only one person was allowed in at a time.
CNN reported on Wednesday night that Mandela was flown from Cape Town to Milpark Hospital and brought to the hospital by military ambulance.
Hospital spokeswoman Erin Walsh would not comment.
“It is our policy to respect patients and we would not give any details about the admission to anyone expect the family,” she said.
The Star reported that a Facebook post by Mandela's granddaughter, Zoleka Mandela, read: “I really hate to see you this way. It kills me each time. Know that i'm here for you as I believe you have always been there for me. You are never alone in this. We are all with you each and every step of the way. All you need to do is remember that you us at your back (sic) and call. I love you. You already know this. Spending my next few days with you just so I know that you'll be ok! I'm saddened... .”
The Foundation issued a brief statement just after 4pm on Wednesday reading: “We can confirm that Mr Mandela is at Milpark Hospital undergoing routine tests. He is in no danger and is in good spirits.”
There had been no further word from the Foundation by 1pm on Thursday. - Sapa