The R24 freeway eastbound between Edenvale road on-ramp and Barbara road off-ramp in Edenvale, Ekurhuleni, has been closed.
Tshwane disaster and emergency management services warned on Sunday that the eastbound lanes had to be closed on Sunday due to massive diesel spillage caused by a five-vehicle crash.
The spillage covers all four lanes for about 800m
Two drivers have been hospitalised.
Motorists are advised to use alternative routes within Edenvale and Meadowdale.
It was unclear when the freeway would be reopened.
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