One person has died and a number of other people have been seriously injured after a lorry collided with other vehicles on the M6 near Lancaster.
An HGV travelling northbound crossed onto the southbound carriageway of the motorway and "collided with a number of other vehicles" close to junction 33, said police.
A Lancashire Police spokesperson said: "Very sadly the collision has resulted in one fatality and a number of other serious injuries.
"Our thoughts are with all those affected at this time.
"Emergency services remain at the scene and the motorway remains closed in both directions between junctions 32 and 33 while we continue to deal with the incident.
"The closure is likely to stay in place for some considerable time so please check before you travel as diversions are in place."
The motorway was closed in both directions on Wednesday morning following the incident close to Junction 33 at south Lancaster. Air ambulances were also called to the scene. Police were called at around 11.20am.
An eye-witness said a wagon had gone through the central reservation into oncoming southbound traffic and there was "absolute carnage".
The M6 was closed between Junction 33 and Junction 32 at the Broughton Interchange and the road is expected to be closed for several hours.
There are severe traffic delays in the area and diversions are in place.
There is also heavy congestion down to Junction 31 at Samlesbury and up to Junction 34 at the Halton Interchange.
Routes through Lancaster, Galgate and Garstang are also heavily congested.
Stagecoach bus services in the Lancaster and Morecambe area have also been affected.
Anyone who witnessed the collision or who has any information can call police on 101 quoting log 0564 of November 6.
You can also email the Serious Collision Investigation Unit at SCIU@lancashire.police.uk
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