De Jong and Gasly ran side by side through Blanchimont with the MP car on the outside early in the race.
The pair rubbed wheels and collided, the contact sending de Jong hurtling towards the barrier on the outside.
The MP Dallara had a high-speed, near head-on impact in which it was engulfed by and rode up on the tyre wall.
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The race was red-flagged and suspended as medical staff worked to carefully extract de Jong from the difficult position in which the car had ended up.
AUTOSPORT understands that the Dutchman was not injured in the crash.
He was taken by ambulance to the medical centre for further checks, with the GP2 Series tweeting that he "is fine and in a good mood".
The race was eventually restarted after a long delay while the ruined tyre wall at Blanchimont was rebuilt.
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