Five people have been killed in a shooting in northern Switzerland, police say, rocking the normally tranquil nation.

The shooter in the incident on Saturday evening (local time) in the town of Wuerenlingen near Zurich, was among the dead, local police head Michael Leutpold told a news conference.

Mr Leutpold said the shooting was linked to a personal conflict.

All the victims and the shooter were Swiss, he said, adding: "We have ruled out a terrorist angle."

He said the shooter was a 36-year-old Swiss national, but he did not reveal his identity.

Local media reports described him as a policeman and father of three.

He did not have a gun licence and did not fire with a police weapon, the police spokesman said.

The shooter first went to a house in a residential area and fired on three people, killing a 58-year-old man, his 57-year-old wife and a 32-year-old man.

The older couple were his parents-in-law and the younger man his brother-in-law, police said.

He then went to another house and shot dead a 46-year-old man before turning the gun on himself.

Neighbours had alerted police after hearing gunshots after 11:00pm.

The latest shooting, which follows similar incidents in January and November, sent shock waves through the tiny Alpine nation.

"This is not possible, we are after all the richest and happiest country in the world," German-language Swiss newspaper Blick said.

In a report published late last month, Switzerland was found to have the world's happiest people, sparking a wave of national pride and media fervour with front-page headlines.

According to unconfirmed estimates, there are up to 4.5 million firearms in circulation in the country.

It is one of the world's top countries in terms of the circulation of firearms, after the United States, Yemen and Serbia.

AFP