Metro Police say the freeway remains closed in both directions between the M7 and M1.
Residents who spoke to Newswatch this morning said they were woken up by a massive explosion just after 4am.
Firefighters managed to extinguish the blaze before 6am.
Luckily, nobody was hurt in the blaze. Metro's Eugene Msomi says the overhead bridge will also need to be inspected.
"There seems to be damage to the overhead bridge, which is Sarnia Road Bridge. We'll have to wait until the engineers come and assess the bridge to make sure that everything is still fine. Other than that we urge people that will be travelling on the N2 to be aware that the road could be closed for quite some time between the M7 and the M1," he said.
Meanwhile, Netcare911's Chris Botha was on scene this morning. This is his account of the fire when he first arrived at the crash site.
"The flames are shooting. Probably about 60, 80 feet up into the air. There's bits of concrete and everything lying all over the road as well, probably it looks like it's from the bridge that runs across the top," he said.
Click here to see more picures from the scene.
(Thumbnail photo:Netcare911, photos: Andreas Mathios, Netcare911)
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