When someone is hit from behind, even at low speed, they can suffer from whiplash, which is caused by a distortion of the neck following a sudden impact.
Some of the possible symptoms that you might suffer include pain and aching to the neck and back, headaches and pain in the shoulders. It may well be that you do not feel symptoms immediately following an accident and it is common for whiplash to delay in presentation by hours or even a couple of days.
In terms of who would be at fault, it seems as though in this case the driver hit the cyclist from behind. This is important, as if somebody goes in to the back of you they are almost always found to be at fault for the accident. Therefore, the cyclist’s family might have a claim for compensation for the death of the cyclist, whose identity has yet to be released.