An unconscious President Bingu wa Mutharika was scheduled to be flown to a hospital in South Africa on Thursday night after suffering a heart attack earlier in the day, Malawi newspapers report.

The Nyasa Times quoted sources at State House as saying that Mutharika collapsed during an appointment on Thursday morning.

He was rushed to the Kamuzu Central Hospital in Lilongwe by ambulance and admitted to its intensive care unit at about 11.35 AM, reported the Daily Times.

A number of high-ranking government officials and First Lady Callista Mutharika, some of Mutharika's children and other relatives were reported to have gone to the hospital, the paper added.

"About three hours later, his son Madalitso was seen leaving the hospital wearing tinted glasses. He was soon followed out by Chief Secretary to the Office of the President and Cabinet Bright Msaka, Minister of Energy Goodal Gondwe and Inspector General of Police Peter Mukhito."

After rumours - including reports of Mutharika's death - swept the capital through the day, Malawi Today said an official government statement was issued on Thursday night confirming he would be taken to South Africa for special treatment.

His illness set off speculation that it could precipitate a leadership crisis in the country.

The vice president, Joyce Banda, who would step into his place if he was unable to perform his duties, is no longer a member of the ruling Democratic Progressive Party. She was expelled, according to the Maravi Post, after she apparently refused to endorse Mutharika's younger brother, Peter Mutharika, as the party's candidate for president at the next election in 2014.