I'm using the Raspbian image 2017-04-10-raspbian-jessie.img
(not Lite) and when I rebooted it today a dialog box came up and said that the system had been upgraded to the latest version, some config files had been overwritten but backed up etc.
But since this Raspberry Pi will be running unattended I don't want automatic updates (also because it actually broke the system and keyboard/mouse no longer works, probably because on bootup it says it failed to start some kernel modules).
How do I disable these automatic updates which obviously is enabled by default?