diff --git a/aws-flow/lib/aws/runner.rb b/aws-flow/lib/aws/runner.rb
index c880399..2579a68 100644
--- a/aws-flow/lib/aws/runner.rb
+++ b/aws-flow/lib/aws/runner.rb
@@ -338,7 +338,15 @@ def self.load_classes(config_path, json_config)
       #
       # @api private
       def self.setup_signal_handling(workers)
-        Signal.trap("INT") { workers.each { |w| Process.kill("INT", w) }  }
+        Signal.trap("INT") do 
+          workers.each do |w|
+            begin
+              Process.kill("INT", w)
+            rescue Errno::ESRCH
+              next
+            end
+          end
+        end
       end
 
       # Waits until all the child workers are finished.