Prior to SQL Server 2012 version, you can stop a running package from the Running Packages folder by right-clicking the package and then clicking Stop. After Project deployment introduced stops a validation or instance of execution in the Integration Services catalog using catalog.stop_operation command in SSISDB Database.
You can find the operation_id from the SSISDB report. Right click on the package that you need to stop and find the operation_id from the report.
Use SSISDB
Exec catalog.stop_operation @operation_id = 159795
Cheers!
Uma
Uma