M1 traffic LIVE: 'Serious collision' sparks 45-minute delays - air ambulance at the scene

The M1 in Bedfordshire is closed northbound between J11A (Leighton Buzzard) and J13 (Milton Keynes) due to a serious collision, National Highways said on Tuesday. The southbound carriage was also closed briefly, to allow the air ambulance to attend the scene.

Emergency services are working at the scene, National Highways said on the afternoon of July 22, with Bedfordshire Police leading the response.

THIS IS A LIVE BLOG. FOLLOW OUR COVERAGE BELOW.