Johannesburg - Democratic Republic of Congo opposition figure Moise Katumbi, President Joseph Kabila's powerful rival who has been charged with undermining state security, has arrived in South Africa for medical treatment, an aide said on Saturday.
Katumbi left DR Congo's second city Lubumbashi on Friday evening, arriving at the airport by ambulance which drove straight up to a waiting plane.
According to airport sources he was accompanied on the flight to Johannesburg by his wife and a doctor.
"He has arrived," said a source in his entourage, speaking to AFP on condition of anonymity, saying the plane on which he arrived was equipped with medical staff and equipment.
Peter Botha, an operations controller at Johannesburg's Lanseria airport said: "A medical plane from Lubumbashi arrived here last night" without saying who was on board.
Aides say Katumbi was injured during clashes between police and thousands of his supporters in Lubumbashi on May 13, with the source saying he was suffering from "respiratory problems" after being teargassed and was "currently under medical observation".
His detractors claim he is feigning medical problems.
His brother Abraham, who was injured after being pelted with stones, is also in Johannesburg, the source said.
The 51-year-old businessman is Kabila's leading rival for the country's top job after recently announcing plans to stand against the long-serving head of state.
Immediately afterwards, judicial authorities on May 4 opened an inquiry, alleging that Katumbi had hired foreign mercenaries.
Katumbi has denied the allegations as "grotesque lies" and said the case, which followed the arrest of four of his bodyguards, including an American, was politically motivated. He was then charged with undermining state security for which he is due to stand trial.
The case against Katumbi comes amid mounting domestic and international concern that Kabila will delay elections due to be held late this year when his second five-year mandate ends.
The opposition claims Kabila, in power since 2001, plans to extend his rule, and last week the Constitutional Court ruled he could stay in office beyond 2016 without being re-elected.