

Detained until it is established that they haven’t committed any crimes. Such is the normal procedure for suspects of murder and other serious crimes.
However there is also people who have refused service, so it is not strictly mandatory, but remains a choice.
The US alone has a prison capacity of about 2 million people. It shouldn’t be too difficult to spread the suspects in prisons around the world. Maybe some people with non-violent offenses such as theft, drug possession or fraud would have to be released on suspended sentences a bit earlier to make space.
However Israel also has a quite large prison capacity. I would argue that the people who run places like Sde Teiman do not have their rights violated if they become inmates there themselves. After all they keep claiming that these facilities are not in violation of human rights.