如果你在公交车上捡到一个包,你会怎么做?用英语回答

If I picked one bag/pocket in the bus,I will take it to the police office and tell the policeman that I picked one bag/pocket in the bus few minutes ago.I don't know who owns it,so I need the policeman help to find out the loser.Most important is that opening the bag tor pocket is not allowed.