A 60-year-old man took two women hostage and then shot them dead before killing himself, Zurich Police said in a statement.
The drama began just before 5.30am on Friday morning when police responded to a call from a woman requiring assistance in Döltschiweg.Street. At almost the same time, a woman in a neighbouring building called saying she had heard shouting.
Police soon arrived on the scene. Some time after, a man made contact with officers by speaking through a window. He said he was holding two women hostage and would kill them if police did not withdraw.
Meanwhile, specialist units and negotiators arrived on the scene.
Some three hours later, at around 8.30am, the man said he would give himself up in ten minutes time. But shortly afterwards, several shots were fired within the residence.
Police entered the building and found three people with serious injuries. All died on the scene.
Investigations into the incident have now begun. The motive for the killings is not known.
The women killed were aged 38 and 34.
“We were told to shut our blinds and remain indoors,” one woman told Swiss news site 20 Minuten. The resident then heard shots. “We were scared.”