Engine keeps running after key is turned off

I need some help my friend just as in yesterday bought a 2010 Wrangler. When he turns the key off the engine keeps running. It will stop after a couple of minutes or if you turn the key back on it will shut off after about 20 seconds.
Any ideas what to check or replace

 

I've never seen that on a jeep before but it sounds like the ignition switch is bad. They are fairly easy to change and around $60 from a napa store. I would start there if it were me.

 

Thanks I will check that

 

Your jeep is possesed lol

 

Awesometimes. It's not knocking and pinging like it's trying to shut down ? Or does it keep running as if you never turned the key off?

 

Ran across this thread after searching the issue im having. What did you figure out with the issue? Im having the same issue that started over the weekend