Zimbabwe Lawyers for Human Rights said police arrested Zimbabwe Congress of Trade Unions members in Harare and the cities of Mutare and Masvingo.
There was a heavy police presence in Harare after the government banned the protest, citing an ongoing cholera outbreak. The lawyers' group said a magistrate dismissed a challenge of the ban.
Zimbabwe now has gas lines snaking for hours, prices spiking and some food and medicines running out. The government calls the problems temporary and a necessary pain in rebuilding the southern African country.
The lawyers called the arrests a pre-emptive strike on the protest against "disastrous economic policies."
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