The three-month orgy of killing was triggered by the shooting down of the plane of then president Juvenal Habyarimana
Swedish police on Tuesday arrested a 48-year-old man suspected of involvement in the 1994 Rwandan genocide which claimed 800,000 lives, police and prosecutors said.
The man, whose identity was not revealed, was arrested at dawn in his house at Orebro, about 160 kilometres (100 miles) west of Stockholm.
The suspect came to Sweden in 1998 and was naturalised in 2006.
The three-month orgy of killing was triggered by the shooting down of the plane of then president Juvenal Habyarimana, a Hutu, in April 1994.
Sweden sentenced to life imprisonment two other naturalised Rwandans Stanislas Mbanenande and Claver Berinkidi, in 2014 and 2016 respectively, for their roles in the genocide.
Similar sentences have been handed down in other European countries, the United States and Canada.