Worcester City Council says it is not aware of any specific terror threats but is taking extra precautions.
The officer shared the information with someone from outside the force, police say.
People were kept away from windows at Perdiswell Primary and Perdiswell Leisure Centre as officers searched woodland.
An assurance of extra spending power for the Midlands leaves Labour unimpressed
A tale of abuse against ambulance workers prompts stories of gratitude
Team news as Leicester host Worcester in Saturday's Premiership fixture at Welford Road (15:00 GMT).
Worcester Warriors flanker Sam Lewis signs a new, undisclosed-length 'long-term' contract.
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