Ugandan opposition leader Bobi Wine was arrested in the capital Kampala on Monday as he took part in a peaceful protest, his office reported on his Twitter. 

The singer, lawmaker and presidential contender had called for protests following a crackdown on his supporters and aides. 

"...He led MPs and other leaders in a peaceful protest against the abduction, torture and murder of his supporters. The protest was taking place at City Square, Kampala," Wine's office said. 

Security forces then reportedly surrounded Wine's house after police took him there following the arrest.

Local media reported that authorities accused Wine of attempting to demolish President Yoweri Museveni's government through leading violent protests. But Wine said he had led peaceful rallies. 

Why is Bobi Wine protesting? 

Footage circulated by local media showed the moment of Wine's arrest while he held a poster saying "bring back our people."

Last week, Wine said it had been 70 days since authorities arrested all of his campaign team members in Kalangala, Central Uganda. 

He reported that thousands of his supporters were in arbitrary detention, calling for their release. 

The presidential challenger was under house arrest in January as he contested the election outcome. A court later ruled against his arrest. 

Wine said he presented evidence that the election was fraudulent after President Museveni, who has been in power since 1985, was declared the winner. 

What was the election outcome?

Museveni won the January 14 elections with 58% of the vote and 35% for Wine, according to final results announced by the electoral commission.

After the election results were announced, security forces surrounded Wine's house to prevent him from leading protests. 

European Union election monitors reported that international observers were excluded during polling. Internet access was also restricted for days before the vote. 

Uganda has never witnessed a peaceful transfer of power since gaining its independence from Britain in 1962.