Drivers were trapped for up to eight hours on the icy A34 in Oxfordshire today.
Police said the northbound carriageway was blocked between the Peartree Interchange and junction 9 of the M40.
Major delays to northbound traffic were caused by various jackknifed lorries and abandoned vehicles.
Police report that some traffic is now getting past the scene, although there are still delays of several hours.
Slow traffic is also reported on the A34 southbound between junction 9 of the M40 and the Milton Interchange, Didcot.
The road is said to be 'just passable'.
The Highways Agency said traffic was 'just about getting through'.
Traffic is also slow on the M40 both ways between junction ten at the Cherwell Valley Services and junction 8A at the Oxford Services.
Traffic is just about getting though single file, but the road is very slippery. No major queues have formed though.
Hazardous driving conditions were reported due to snow and ice on roads around Oxfordshire.
Most roads in Oxfordshire are said to be very slippery.
Minor roads may be impassable in places.
Ice is reported on the A417 Lechlade Road, Faringdon, between Canada Lane and A361 Burford Street.
- What are conditions like in your part of the county? Post your comments below.
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