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HARARE (Reuters) -Zimbabwe police have arrested opposition leader Jameson Timba and 80 youths for holding a political gathering which authorities said was unauthorized, their lawyer said on Monday.

Timba took over as interim leader of Citizens Coalition for Change after former leader Nelson Chamisa quit the party in January, alleging it had been hijacked by the ruling ZANU-PF party.

The arrests were made on Sunday.

"They are still in custody and we are working on their release. They are likely to be charged with maintenance of public order laws," lawyer Agency Gumbo told Reuters.

CCC party spokesperson Promise Mkwananzi said the arrests were "regrettable" and showed "democratic regression".

Police were not immediately available for comment.

The law requires that political parties apply for clearance with police before holding a public gathering. Sections of the law have been used in the past to clamp down on the opposition and ban political rallies.

(Reporting by Nyasha Chingono; Editing by Olivia Kumwenda-Mtambo and Christina Fincher)