Yusuf 12:35

Thumma bada lahum min baAAdi maraawoo al-ayati layasjununnahu hatta heen

Then it appeared to them after they had seen the signs that he [i.e., al-ʿAzeez] should surely imprison him for a time.

Later on, even after having seen the clear signs (of his innocence), they deemed it proper to imprison him for some time.