Massive London Explosion Sends People Into Panic, Preplanned Fire Got Out of Control

A huge fireball just exploded in East London ... but, cops are telling people not to worry -- 'cause it's all just movie magic.

Here's the deal ... a few hours ago, a massive explosion rocked Londontown -- drawing eyes and phone cameras from around the city capturing the wild scene.

The huge black smoke and bright orange flames caught a lot of people's attention ... and, they took to X to alert police, news agencies and other Londoners to what they saw.

Nothing to worry about though, cops released a statement to the public saying they knew about the explosion ... which was totally preplanned as part of filming in the neighborhood, and did not pose a risk to the public.

The London Fire Brigade had a slightly less rosy view of the situation ... admitting the explosion was preplanned for the filming -- but, it did get a little out of hand.

That said, LFB says they worked quickly to put the fire out and would remain on-site through the evening to keep an eye on the situation.