Delays are currently building by the A414 near Hatfield after a lorry overturned.
Police were called to Oldings Corner at 8.01am following reports that a tipper lorry had overturned whilst heading towards the stretch to Hertford.
A police spokeswoman said there is currently rubble on the carriageway and the vehicle remains on its side. She added that officers are still at the scene but no-one is thought to have been injured.
Motorists are being advised to plan ahead before using the route.
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