SIR – So the spotting of a woman entering a compound on a Bingley Industrial Estate at 4:35am warranted the scrambling of the police helicopter (T&A, February 19)? Officers, both on the ground and in the air, found no-one. Words fail, other than to warn all those early morning starters and finishers – cleaners, postal workers, milkmen and women, shift workers etc – to watch their step lest they think World War III has started or they are about to be abducted by aliens as they make their way to or from work.

A Waterhouse, Barmby Road, Bradford