Police have confirmed why their helicopter was hovering over the city yesterday.
Officers were called to East Street in Chichester just after 1pm yesterday.
They were responding to reports of abusive street drinkers, police confirmed.
However it eventually came to light that the National Police Air Service (NPAS) helicopter was called in for something else, but it was not immediately clear what for.
Police confirmed on Twitter this morning that the helicopter was assisting them trace a missing person.
To report crime call 101 or visit the Sussex Police website.
In an emergency always dial 999.