BERLIN (AP) — Authorities in Germany believe antisemitism was one of the factors that led a man near Berlin to kill four members of his family and then himself last year.

The bodies of the man and his wife, both aged 40, and their children aged 10, 8 and 4 were discovered with gunshot wounds at their home in Brandenburg state on Dec. 7, 2021. Prosecutors said at the time that a note also found at the house in the town of Koenigs Wusterhausen indicated the man was afraid a forged coronavirus vaccination certificate would result in their children being taken away.

Germany’s Interior Ministry said in a written reply to Left party lawmaker Petra Pau that investigators found chat messages showing the father believed the state's vaccine campaign was part of a plan “to halve the world population and establish a new world order under Jewish leadership.”

Judith Porath, who heads a group that helps victims of far-right violence in Brandenburg state that published extracts from the letter Friday, said the incident showed the extent to which antisemitic conspiracy theories have spread among those opposed to government measures against the coronavirus pandemic.

She called for authorities to continue their investigation into the case to determine how the man became radicalized and whether others knew of his plans.

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