The Toontown area of Disneyland had to be evacuated on Tuesday after dry-ice in a bottle exploded in a rubbish bin.
The "small blast" went off in Mickey's Toontown at around 5.30pm local time, and Disneyland officials took to their Twitter account to say that "in an abundance of caution, the area was evacuated", reports ABC News.
Park visitor Allen Wolf said he was about 20ft from the blast, which he said "sounded louder than a gunshot", but similar.
There was no damage or injuries caused by the blast and, after a two-hour investigation by Anaheim police and an Orange County sheriff's bomb squad, the area was deemed safe for tourists to return.
Anaheim police sergeant Bob Dunn said the incident was a scary prank, but that it would be taken very seriously.
He told LA Weekly: "We have responded to these types of incidents in our neighbourhoods where these people have done this. Our officers generally know what they're looking at."
He also explained to the site exactly how the dry-ice blast works, saying: "When you put the dry ice inside the water bottle it expands and it makes the air want to escape. You put the lid on and it keeps expanding and the bottle fails and you have an explosion-type noise."
He added that the escaping dry ice creates a smoky effect, which further scares people following the noise of the blast.
According to its website, Disneyland describes Mickey's Toontown as "an interactive metropolis full of topsy turvy architecture and screwy sculptures".
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