Kampala, Jumada I 06, 1437, February 15, 2016, SPA -- One person was killed, an unknown number injured and more than 20 arrested Monday as Ugandan demonstrators clashed with riot police following the arrest of a top opposition candidate in this week's presidential elections, police said, according to dpa. Kizza Besigye, the main challenger to President Yoweri Museveni, was arrested after marching with thousands of supporters to a rally ground in the capital, Kampala. He chose a route different from the one which had been designated for him by police, who fired tear gas and rubber bullets to disperse his supporters. Besigye was detained but released soon afterwards, said Wilberforce Kyambadde, the head of his campaign team. Protesters then waged running battles with police in several suburbs, throwing stones and burning tyres. "One person died, but we are yet to confirm the cause of the death ... I cannot tell the number who were injured, but we arrested about 21 people," deputy police spokesman Patrick Onyango said. The arrest was the second for Besigye ahead of Thursday's presidential and parliamentary elections. --SPA 22:10 LOCAL TIME 19:10 GMT www.spa.gov.sa/w