A police helicopter hovered over a city street in a late-night search for a cannabis factory.
The airborne patrol used heat-seeking equipment to scan the roofs of houses on Upper Lewes Road, Brighton.
Residents reported a "deafening racket" several streets away as the helicopter spent about 20 minutes in the sky above the area between half past midnight and 1am this morning.
The police team was following up a report of a "weird smell", thought to be cannabis, from a policeman on the ground.
Hydroponic lamps used to grow cannabis plants use a large amount of power and use a lot of heat.
The police helicopter's heat-seeking device found unusually high temperatures in the roof of a house at the Ditchling Road end of the street.
Police checked the property, but they found nothing suspicious.
Mel Nowocin, who lives in nearby Ditchling Rise, said: "It was loud, even through my double glazing.
"At that time of night you would have thought they would be a bit more considerate."
A spokesman for Sussex Police said: "The helicopter is up there at all sorts of times.
"In this case they found a house with a very warm roof, but everything was in order."
12:57pm Friday 30th March 2007