Warner Bros Studios has confirmed why there were "ground shaking explosions" earlier today. 

A resident contacted the Watford Observer reporting what happened alongside a picture of black smoke rising into the sky.

The bangs, which happened at around 9am (September 28), were in relation to a production which is currently underway, the Leavesden studios confirmed.

However, it did not share which production it was linked to.

Watford Observer:

The studios told the Watford Observer that residents living nearby were given a letter explaining the special effects which are happening.

Warner Bros Studios expansion

It comes as the studios recently said its expansion will "create 4,000 jobs" nationwide and contribute "more than £200 million" to the UK economy.

The firm behind the Harry Potter film franchise is also set to become a primary production hub for DC Studios as part of a boost for the UK film and TV industry.

Groundbreaking on the project is set to begin next year, with the expansion expected to be completed in 2027.

The majority of the expansion will be in the Three Rivers district with 10 per cent of it in Watford.

Films which have been created in Leavesden include Barbie, Paddington 2, Meg 2: The Trench, and Wonder Woman 1984.