Obviously something was off, the jars either didn't seal properly, weren't heated thoroughly, the ph was off or they came unsealed. Either way the bottoms of the jar turned milky, the lids popped up, as soon as the rings were loosened the tops popped open and fizzed. All roads point to fermented. It happens. Toss them and try again next year.
You can see the tiny bubbles in the top photo and the larger ones on the bottom. This is not was is supposed to happen! Sure, it sucks and is a waste but it's better than poisoning yourself.