Uganda opposition presidential candidate Robert Kyagulanyi, popularly known as Bobi Wine, and his campaign team were arrested in the country's central region on Wednesday, he said on Twitter.
No further details of their arrest were immediately available. They were arrested in Kalangala in central Uganda, Wine said in the post.
Joel Senyonyi, spokesman for Wine's party, the National Unity Platform, said: "Yes police has arrested him together with his whole campaign team. They (police) put them in police trucks and started driving but we don't know where they are taking them."
Police spokesman Fred Enanga was not immediately available for comment.
Wine has emerged as the strongest challenger to President Yoweri Museveni, 76, in the presidential election on Jan. 14.
In November, at least 54 people died after protests erupted following Wine's brief detention over alleged violation of COVID-19-related social distancing measures.
Police said at the time they had arrested nearly 600 people and accused protesters, whom authorities had enlisted the help of the military to disperse, of rioting and looting.
On Tuesday, United Nations human rights experts called on Uganda to rein in violent security forces and drop charges against political opponents and activists arrested in what the experts called an election clampdown.