At least one person has died in riots in Uganda's capital over the treatment of opposition leader Kizza Besigye. Security forces have fired live ammunition, rubber bullets and tear gas to disperse protesters burning tyres. Mr Besigye sought medical treatment after being tear-gassed in his car and bundled roughly into a truck when he was arrested on Thursday. It was his fourth detention this month for his participation in a "walk-to-work" protest over high prices. President Yoweri Museveni has said the walking campaign over the rise in the cost of living is illegal. After his arrest Dr Besigye was charged with inciting violence but released on medical grounds until 2 May. The BBC's Joshua Mmali in the capital, Kampala, says he was taken to hospital from the court because he had been blinded by the tear gas and pepper spray. Dr Besigye's lawyer has told the BBC that the Forum for Democratic Change leader was discharged on Thursday night from hospital, but he was not able to reach him by phone on Friday morning. Rumours spread According to Uganda's Red Cross, one person has died in the trouble. "One person passed away from bullet wounds in the suburb of Bwaise," Red Cross spokeswoman Catherine Ntabadde is quoted by AFP news agency as saying. "Fifty people have been taken to hospital mainly due to tear gas and bruises." A witness told Reuters news agency they had seen someone lying in a pool of blood at a local market after being shot in the head. Our correspondent says transport has been paralysed, shops remain closed. Earlier on Friday morning, gunshots could be heard from different parts of the city and live ammunition was shot into the air in some areas. The trouble started in Kisseka market after rumours spread that the FDC leader may have died. The speculation about his death spread via Twitter and on Uganda chatrooms. The security forces are out in strength as the trouble spread across the city, our reporter says. In some areas, the military are now forcing people out to clear up the roads where blockades were set up and tyres burned, he says.