The arrests were the latest sign of tension in the central African country before the October 9 vote which pits long-serving leader Paul Biya against nearly two dozen opposition candidates.
“As I am speaking to you, 150 of them are held at (the mobile intervention unit), 30 at the central police station and 25 at the gendarmerie brigade,” the source said, asking not to be named because he was not authorized to speak publicly.
Security forces cracked down after members of the Anglophone separatist movement, Southern Cameroons National Council (SCNC), attempted to hold an illegal rally on Saturday in the southern town of Buea, sources said.
The SCNC, which seeks independence of the region, considers October 1 as the symbolic date when it believes it was denied the option to secede in a referendum that united British southern Cameroon with the former French Cameroon in 1961.
Last week, armed men wearing combat fatigues fired shots from the main bridge in the economic capital Douala, an incident apparently unrelated to the separatists, but which ramped up tensions leading into the elections. One official said one of the gunmen held a banner calling for Biya to quit.
Biya, one of Africa’s longest serving presidents, is widely expected to win the vote in the oil-producing nation though his critics say he has rigged the election in advance through his tight control of the electoral commission.
Created in 1995, the SCNC is an umbrella grouping of several separatist movements of Cameroon’s English-speakers that want independence of their territory. They have long complained of being politically marginalised and neglected by authorities in the capital Yaounde.