Get breaking news alerts and special reports. The news and stories that matter, delivered weekday mornings.

AARAU, Switzerland — A gunman killed three relatives and a neighbor in a late-night rampage in a Swiss village before turning his weapon on himself, local police said on Sunday.

The presumed killer, a 36-year-old Swiss national who was separated from his wife and the couple's three children, shot dead his father-in-law, mother-in-law and brother-in-law, police told a news conference.

The killings took place late on Saturday in and around a residential building in Wuerenlingen, a community of some 4,500 people north-west of Zurich.

Police said the gunman lived in another part of Switzerland and was known to police for violent behavior. The murder weapon was unregistered, they said.

A neighbor, who was not identified, told Swiss newspaper Blick she heard four shots in succession fired very quickly, then two further shots after a pause. She had heard no screams, the tabloid reported.

Swiss police attend the scene of the fatal shootings in Wuerenlingen. ANTHONY ANEX / EPA

— Reuters