Protest action has been reported at Bruntville near Mooi River on Monday and on the R103 on the Lions River bridge.
The R622 Greytown road is blocked, with SA Emergency Reports cautioning that "due to mist, this isn't visible until you are almost upon the protesters".
Motorists are urged to avoid this road until further notice.
The N3 and R103 remain open.
Protesters are also burning tyres and blocking the R103 and the D369. The suggested alternative route is via Balgowan.
TimesLIVE
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