Both carriageways of the A1(M) have now been reopened after a collision earlier this morning.
The northbound carriageway of the A1(M) between junctions three for Potters Bar and St Albans and four for Hatfield has now been reopened.
Emergency services were initially called to reports of multi-vehicle collision involving three cars at about 9.05am.
But on arrival they found only a blue VW Polo was involved in the crash inside the tunnel travelling northbound.
Southbound traffic began to move again at around about 9.45am.
Emergency services have now left the scene.
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