Neighbours in Ipswich have reported hearing a loud bang coming from Stonelodge Park in Chantry.
Residents posted on social media to question where the noise came from, with some speculating it was a firework.
It was heard throughout the neighbourhood, from as far away as Chantry Academy, Newnham Court and Kingfisher Avenue.
One social media user commented that the sound was "like a fighter jet breaking the speed of sound", while another claimed it could have come from a lorry collision.
A spokesman for Suffolk police confirmed officers had not received reports of any incident in the park.
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