Samsung Galaxy s3 mini continuously rebooting

I woke up to find My Samsung Galaxy s3 mini asking me to select a language and time and sign into my Samsung account, like it was a brand new phone. As I tried to do this it kept rebooting. eventually I managed to sign in, but it continues to reboot every minute or so and a few of my widgets are missing. After researching I uninstalled the Samsung push app but it keeps going back to the sign in start page, but it reboots before I can sign in and there is no way to skip it. I have removed my battery, SIM card and SD card, but it is still happening. I also tried a factory reset, but every time I click on it me phone restarts and nothing has changes. Does anyone know what is going on or what I can do to stop it rebooting?