The article says witnesses claim the tanker was too tall for the clearance. Or so they say.
The police have also indicated that they believe the tanker truck took the wrong exit, or was forced (stuck in wrong lane) to take the exit.
IMHO, so far, it does not appear to be a planned action. It appears to be a deadly mistake.
They can't get close enough, due to the intense heat, to even tell how many cars , trucks, fire trucks, people are involved in this.
If no one has died in this, it will be a miracle.
Really hard to believe! We've had a 14' clearance standard since 1955.