What will you do if u get a tipoff of the crime activities that is going to happen?

It depend with the duration or time when the crime is going to happen.if there's enough time, I will report to my superior according to chain of command,so that he/she will take immediate action to prevent the crime to happen.But if the crime is going to happen within the shortest time eg you have been informed that  the terrorist have been spotted in a building planting bomb in that building, you need to take immediate necessary action to counter attack those terrorist and then report the incident later after everything has cooled down.