Police in Zimbabwe have raided the headquarters of the opposition Movement for Democratic Change (MDC) in Harare and arrested as many as 200 activists.
Zimbabwean police have cracked down on MDC activities
The activists were taken away in police vans, though the MDC's Nelson Chamisa said police had no search warrant.
Mr Chamisa told the BBC that the meeting was held in party offices to discuss civil issues and insisted the MDC was doing nothing illegal.
The arrests came a day after police extended a ban on political rallies.
The BBC's Peter Greste, in South Africa, says the police cordoned off a number of blocks around Harvest House and burst into the party headquarters, beating and arresting anyone they found inside.
Mr Chamisa said those inside the building had included the MDC's youth council and another urban council.
Mr Chamisa said those detained had been taken to the notorious Law and Order division of the Central Police Headquarters. No senior party leaders were said to be in the building at the time.
In the past, party activists have been arrested for violating a ban on political gatherings and for allegedly planning acts of terrorism.
South Africa is currently trying to negotiate a political solution to Zimbabwe's escalating crisis. Diplomats say Zimbabwe is in danger of breaking into open conflict, our correspondent says.
Mr Chamisa said the police raid showed the government's disdain for the diplomatic efforts.