Representatives of the Zimbabwe Congress of Trade Unions (ZCTU) say the group's president and secretary-general were severely beaten during Wednesday's failed protests.
Union leaders say police used batons and rifle butts to beat union activists, including President Lovemore Matombo and Secretary-General Wellington Chibhebe as they gathered to march on Wednesday. The ZCTU says authorities have arrested some 270 union officials and protesters, and were continuing to arrest people on Thursday.
An attorney for the labor leaders, Alec Muchadehama, told the Associated Press that police have acknowledged that several union leaders need medical attention and have promised to escort a group of 16 activists who are being held in prison to a state hospital.
In an interview with VOA, Zimbabwe's Acting Information Minister Paul Mangwana responded to the allegations of assault, saying you disperse illegal demonstrations with baton sticks, not whistles.
The government declared Wednesday's planned marches illegal ahead of time, and placed heavy security on the streets to prevent any protests from starting.
The union had planned marches in cities across Zimbabwe to protest low wages, high taxes and workers' lack of access to anti-retroviral drugs that fight AIDS.
The unions are allied with Zimbabwe's splintered opposition party, the Movement for Democratic Change. Earlier this year, the party issued its own call for anti-government protests that have yet to materialize.
Zimbabwe is reeling from the effects of high inflation, record unemployment and severe shortages of food, fuel and foreign currency. The nation's agriculture-based economy has been in a freefall since the seizure of thousands of white-owned commercial farms beginning in 2000.
Some information for this report was provided by AP and Reuters.