M1 | Greater London | Road Closure | Expect Del… — Cleared 17 Aug

What happened

The M1 in Greater London is closed southbound between J4 (near Borehamwood) and J1 (near Wembley) for a police led incident

RoadM1

SeveritySevere

StatusCleared

DirectionSouthbound

Started21:08, 17 Aug 2026

Cleared23:16, 17 Aug 2026

21:08, 17 AugFirst report
The M1 in Greater London is closed southbound between J4 (near Borehamwood) and J1 (near Wembley) for a police led incident
21:21, 17 AugUpdate
The M1 in Greater London is closed southbound between J4 (near Borehamwood) and J1 (near Wembley) for a police led incident
21:51, 17 AugUpdate
⏱ Still active — no changes from National Highways. Incident ongoing for 43 minutes. Monitoring continues.
21:56, 17 AugUpdate
The M1 in Greater London is closed southbound between J4 (near Borehamwood) and J1 (near Wembley) for a police led incident
22:31, 17 AugUpdate
⏱ Still active — no changes from National Highways. Incident ongoing for 1h 23m. Monitoring continues.
22:36, 17 AugUpdate
The M1 in Greater London is closed southbound between J4 (near Borehamwood) and J1 (near Wembley) for a police led incident
23:06, 17 AugUpdate
⏱ Still active — no changes from National Highways. Incident ongoing for 1h 58m. Monitoring continues.
23:11, 17 AugUpdate
The M1 in Greater London is closed southbound between J4 (near Borehamwood) and J1 (near Wembley) for a police led incident
23:16, 17 AugUpdate
✅ Incident cleared — M1 reopened at 23:16 on 17 Aug 2026. Total disruption: 2h 8m. All lanes open, traffic returning to normal.
17:02, 5 NovFinal update
The M1 in Greater London is closed southbound between J4 (near Borehamwood) and J1 (near Wembley) for a police led incident

Wording from National Highways, recorded as it changed.

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