Thread was being aborted Exception is thrown in Business logic

Hai
In my application i have wriiten a logic for processing. this process is called by a webservice which is resides in the same IIS. In my code i didn't use response.redirect or server.transfer in my business logic. But still i get the follwing exception.
Error Number: 5
Error Description: Thread was being aborted.
Exception Message: Thread was being aborted.
Exception Type: System.Threading.ThreadAbortException
Base Exception: Thread was being aborted.
Base Exception Type: System.SystemException


Any one tell me the reason for this issue?  And How can i solve this ?


Thanks
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