Thorpe Park has reportedly been put on lockdown as emergency services rush to the scene. Visitors have been tweeting about the incident and claiming there have been reports of a stabbing - although this has not been confirmed.
Photos from the scene show a heavy police presence and a large crowd of people all gathered together. A father who is at the popular attraction with his kids said he saw paramedics attending to a patient on the bridge.
One mother said her daughter is at Thorpe Park and has been told she can't leave. Some reports claim people have since been allowed to leave - but say that there are huge queues to get out.
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