The closure was put in place on the eastbound carriageway at junction 7 (Hyndburn Interchange), near the roundabout, at around 4.30pm today (January 20).
Police urged motorists to avoid the area while emergency services attended the scene of the incident.
"An update will be provided when the road is reopened," a spokesman for Lancashire Police added.
Heavy traffic was building following the closure, with congestion building on surrounding roads.
More to follow...
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