Parents of pupils at Haworth Primary School have been asked to be vigilant following reports that children have been followed to and from school.
Pupils at the school, which is in Rawdon Road, have also been told how to stay safe and how to behave if approached by a stranger.
Parents have been sent a letter warning them of the potential threat.
A spokesman for West Yorkshire Police confirmed officers had been called to the school and were currently looking into reports of children being followed.
Full stopry in this week's Keighley News
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