Both sides of the M6 between junctions 14 and 15 in Staffordshire were shut after a HGV caught fire at around 5.30am.
Police attending the scene reported that cans of dog food were continuing to explode over the carriageway up to two hours after the blaze started.
Pictures from the scene show steaming cans spilling out of the lorry's charred remains. The southbound lanes were quickly opened up after half-an-hour, but emergency services have so far only been able to reopen one northbound lane.
Central Motorway Police Group tweeted: "M6 Nb closed. Everything diverting off at j14 onto the A34. Some of the tins of dog food are still exploding."
The M6 has been closed after a lorry fire caused tins of dog food to explode
The motorway was closed between junctions 14 and 15 in Staffordshire
Highways England tweeted: "Staffordshire We've opened 1 lane £M6 northbound between J14 and J15 past the scene of the HGV fire."
Firemen from Staffordshire Fire and Rescue also attended the scene.
A spokesman for Highways England said: "The M6 in Staffordshire is closed northbound between J14 and J15 due to a Heavy Goods Vehicle fire. Staffordshire Fire and emergency services are currently on scene.
Pictured show the exploding cans spilling out of the remains of the lorry onto the road
"Road users are advised to follow the Hollow Triangled diversion symbols exiting the M6 northbound at J14 then take the exit to the A34 (northbound).
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"Continue along the A34 to the junction with the A500 (Hanford). Take the exit on to the A500 (Westbound) and continue until you rejoin the M6 at J15.
"Road users are advised to allow extra time for their journey."