Suspended Makerere Institute of Social Research (MISR) lecturer Dr Stella Nyanzi has been arrested as she attempted to enter FDC offices in Najjanankumbi.
Police deployed early in the morning at FDC offices to block the weekly prayers.
FDC lead pastor Happy Ngabo and his co-pastor Edward Ssenyange who had also gone for the prayers were arrested and locked away.
Opposition leader Kizza Besigye in a tweet said Pastor Happy Ngabo who was supposed to lead the Tuesday prayers was roughed-up and is now detained at Katwe Police Station.
Besigye called on supporters to “go to rescue him”.
Meanwhile two journalists were earlier arrested while those at the FDC head offices were also ordered by police to leave the premises.
Police deputy spokesperson Polly Namaye, had warned opposition against holding defiance activities which were last week banned by court.
On Friday, Justice Kavuma issued an interim order blocking Dr Besigye’s planned peaceful demonstrations at Nakivubo Blue primary school on May 5.
FDC party president Maj Gen Mugisha Muntu on Monday said no one had a right to block prayers and that they would continue with their programme.
Police is now deployed at most FDC offices across the country as part of the security ahead of President Yoweri Museveni’s swearing in slated for May 12th.