How to end session in asp.net when browser is closed ??

Question

Hi,

I want to update user logout details like time,status, etc when a user logged out from my application. So I handled Session_End event and updated the logout details.
If the user properly clicks on logout button, there is no problem.

My problem is, if the user closes the browser directly i need to force the session end to fire.
How to do that.
I had used master page in my application.

Kindly help.