Brandenburg an der Havel
In November 1938 Heinze took over the direction of the "Landesanstalt Brandenburg-Görden" otherwise "Landes-Pflegeanstalt Brandenburg an der Havel", a mental institution at Brandenburg an der Havel, housed in the old Brandenburg an der Havel Prison, commonly now referred to as the Brandenburg Euthanasia Centre, with about 2,500 patients, 1,000 of them children. Here he supervised the murder by injection, starvation and poisoning of thousands of children whose brains he then supplied to Nazi researchers. He also trained physicians for the T4 Euthanasia Programme.