You think the charges are invented? Why?
It's important to realize that anytime you give the police power over people still facing trial, you give them that same power over anyone they can fabricate spurious charges against. That's why it's important to have things like warrants and pre-trial court orders, so that there's some accountability when the police detain someone over unproven allegations.
But still - it doesn't matter whether the charges are invented or not, or even what those charges are. What matters is that a judge (not the police) ruled that he should be held until his trial.