Zimbabwe's opposition party leader Morgan Tsvangirai and 11 members of his presidential election campaign team were detained by police on Saturday, the Movement for Democratic Party (MDC) said.
The 12 were detained at a roadblock just outside the town of Shurugwi in the south of the country, party spokesman Nqobizitha Mlilo was quoted as saying by South Africa's Sapa news agency.
"They were taken to Shurugwi police station where they are currently being detained. At this stage we do not know the reason for their detainment," Mlilo said.
Police have detained Tsvangirai on at least four previous occasions in the last two weeks, holding him for several hours before releasing him without explanation or charge.