The loud squawking noise came in the middle of the night.
For a week a middle-aged couple in Wacken, a village in the state of Schleswig-Holstein in northern Germany, were woken by the piercing crowing of a cockerel.
Eventually Jens Nagel and his wife complained to the police, but despite three separate visits to the house, officers were unable to find the bird.
It was only when they returned with a warrant and searched the neighbouring flat that they solved the mystery, discovering a stereo system with its speakers bolted towards the wall.
Inside was a tape-recording of a crowing cockerel and a sophisticated timing device which played the tape between 2am and 4am, at 20-minute intervals. The Nagels shared two halves of a detached house and the speakers were pointed at the their bedroom.
On Wednesday the police said it was not clear why the neighbours, who had gone away on holiday, had done it.
Rows between neighbours are common in Germany, but there was no previous history of disputes between the couples, a police spokesperson, Stefan Hinrichs, told The Guardian on Wednesday.
Environmental health officers measured the crowing at 100 decibels, well above the tolerated level of 60 decibels.
The Nagels’ neighbours have not returned from their holiday, and when they do they will be charged with causing a breach of the peace and actually bodily harm, and will be liable to heavy fines, Hinrichs said. – Guardian Unlimited Â