A fire has spread across an extensive area of vegetation on mountain slopes along Sir Lowry's Pass, the City of Cape Town said on Tuesday.
Twelve firefighting vehicles were currently on scene, City of Cape Town Fire and Rescue spokesperson Theo Layne said.
City of Cape Town safety and security director Richard Bosman said the N2 was closed between Sir Lowry's Pass Rd and Botrivier.
There was also no access to Gordon's Bay Rd and Sir Lowry's Pass Village and all outgoing traffic was required to make a U-turn at Sir Lowry's Rd intersection.
Further road closures would follow.
"No heavy duty trucks or busses will be able to travel through the R44 Rooi Els due to the road works," Bosman added.
A thick cloud of smoke was also seen hanging over the Cape Town CBD.