What happened
The M25 in Hertfordshire is closed in both directions between J21a (St Albans) and J22 (London Colney) for a police led incident
RoadM25
SeveritySevere
StatusCleared
DirectionBoth directions
Started19:15, 28 Aug 2026
Cleared23:51, 28 Aug 2026
Incident timeline
First report
The M25 in Hertfordshire is closed in both directions between J21a (St Albans) and J22 (London Colney) for a police led incident
Update
The M25 in Hertfordshire is closed in both directions between J21a (St Albans) and J22 (London Colney) for a police led incident
Update
⏱ Still active — no changes from National Highways. Incident ongoing for 50 minutes. Monitoring continues.
Update
The M25 in Hertfordshire is closed in both directions between J21a (St Albans) and J22 (London Colney) for a police led incident
Update
⏱ Still active — no changes from National Highways. Incident ongoing for 1h 25m. Monitoring continues.
Update
The M25 in Hertfordshire is closed in both directions between J21a (St Albans) and J22 (London Colney) for a police led incident
Update
⏱ Still active — no changes from National Highways. Incident ongoing for 2h 0m. Monitoring continues.
Update
The M25 in Hertfordshire is closed in both directions between J21a (St Albans) and J22 (London Colney) for a police led incident
Update
⏱ Still active — no changes from National Highways. Incident ongoing for 2h 35m. Monitoring continues.
Update
The M25 in Hertfordshire is closed in both directions between J21a (St Albans) and J22 (London Colney) for a police led incident
Update
⏱ Still active — no changes from National Highways. Incident ongoing for 3h 10m. Monitoring continues.
Update
The M25 in Hertfordshire is closed in both directions between J21a (St Albans) and J22 (London Colney) for a police led incident
Update
⏱ Still active — no changes from National Highways. Incident ongoing for 3h 50m. Monitoring continues.
Update
The M25 in Hertfordshire is closed in both directions between J21a (St Albans) and J22 (London Colney) for a police led incident
Update
⏱ Still active — no changes from National Highways. Incident ongoing for 4h 25m. Monitoring continues.
Update
The M25 in Hertfordshire is closed in both directions between J21a (St Albans) and J22 (London Colney) for a police led incident
Update
✅ Incident cleared — M25 reopened at 23:51 on 28 Aug 2026. Total disruption: 4h 35m. All lanes open, traffic returning to normal.
Final update
The M25 in Hertfordshire is closed in both directions between J21a (St Albans) and J22 (London Colney) for a police led incident
Wording from National Highways, recorded as it changed.
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