Armed police patrolled the Zimbabwean capital Harare on Monday as frustrations grew over a deepening economic crisis.
President Robert Mugabe's government has routinely used police to break up opposition rallies and protests against a crisis that has left many Zimbabweans scrounging for food and medicines as health and education services collapse.
On Monday, dozens of riot police were stationed at a central city park where protesters usually gather for marches.
Other police squads with batons, shields and teargas canisters patrolled Harare on foot, although there was no public announcement or visible sign of planned protests.
There was no comment from police on the deployment. Public anger is high over an economic meltdown that has brought 80 percent unemployment, chronic shortages of food and fuel, hyperinflation and an outbreak of cholera.
Mugabe -- who is on leave this month and returned home on Saturday from a week's vacation in Southeast Asia -- says Zimbabwe's economy has been sabotaged by Western powers opposed to his seizures of white-owned farms for blacks.
A power-sharing deal signed between Mugabe's ruling ZANU-PF and Morgan Tsvangirai's opposition MDC in September has not been implemented as the sides argued over control of ministries and the abductions of opposition figures and human rights activists.
On Monday, the Reserve Bank of Zimbabwe announced that it would let workers with payslips cash their salaries without limit, while all other withdrawals remained restricted.
Zimbabwean dollar salaries are now mostly being used to pay for public transport, but many businesses are demanding payment in foreign currency in the face of inflation that officially stands at over 230 million percent.
Critics say Mugabe -- 84 and in power since independence from Britain in 1980 -- has mismanaged the economy.
A cholera outbreak has worsened the humanitarian crisis, infecting nearly 40,000 people and killing more than 1,800.