Dear Nitya.,
I think they told why shaan was kept in jail.,even after knowing he is shantanu.K.I think the police inspector who called the local police constable said that if he did not find out both he is in the danger of losing his job.By the time khanak was already let off.
Now they showed the constable talking to himself and saying that till he finds out khanak he could not let out shaan (otherwise he would end up searching both.,now he has atleast one in the jail)
The constable left for searching her and khanak after wandering for a while came back.It is obvious that the constable has not seen her.
The rapist part and shaan being suddenly taken off by the comment was very good.