A massive bomb explosion scene from Transformers: Age of Extinction was filmed at a grain silo site in Chicago on Oct. 3.

Director Michael Bay promised "[the] mother of all" explosions to be featured in the movie, calling the attention of fans as the production crew constructed a fictional destruction sequence. In the video, taken from a local who saw the scene take place, it seems like the explosions happened on a patch of land in front of the grain silos and did not cause any real damage to the buildings, but very effectively created the illusion of obliteration.

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The clip begins with a helicopter hovering above the location, capturing an aerial view of the spot before the explosions went off. Shortly after, fire gained heft with massive clouds of bellowing smoke obscured the towering buildings as a series of bombs were set off.

The grain silo site is also being used as a stand in for Hong Kong in the Transformers film.

In August, fans were treated to glimpses of filming in downtown Chicago in August, where Bay and his crew set off fireworks with staged explosions at the McCormick Place Plaza. The team also staged controlled pyrotechnic explosions in Detroit that same month.

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Jack Reynor is the male lead of the film and will be playing a race car driver. Nicola Peltz acts as Reynor's girlfriend in the film and Wahlberg will portray Flynn Vincent, Peltz's dad.

Kelsey Grammer was the most recent addition to the cast. He will be playing the role of Harold Attinger, a counter-intelligence agent who is the main antagonist in the film. Grammer spoke about his character to Empire magazine in September.

"He's a no-nonsense guy. He's lived his life in the shadows for 30 years in the service of his country, and he likes to be unremarkable yet very efficient." he said of Harold.

Transformers: Age of Extinction is out in theaters June, 27, 2014.

Watch the explosion: