"These abductions and torture will not take us anywhere," Bright Matonga said on South African public radio, vowing that the authorities would investigate the allegations.
He also called on the opposition Movement for Democratic Change (MDC) to join a unity government, as South Africa prepared to lead a new round of talks on a power-sharing deal in Harare on Monday.
"We cannot go it all alone. This is the point we are making. We need the MDC," Matonga said, in an unusually conciliatory statement from President Robert Mugabe’s government.
South African President Kgalema Motlanthe will go to Harare with former president Thabo Mbeki and Mozambique’s President Armando Emilio Guebuza to try to revive the unity accord signed four months ago but never implemented.
MDC leader Morgan Tsvangirai has warned that the arrest and beatings of activists violate the pact, which guaranteed freedom of political activity and expression.
Human Rights Watch says 32 opposition activists have been abducted and often beaten by security forces since October, while the MDC says 11 of its members are missing. – AFP