The Angel of Highway 19

On a remote stretch of Highway 19 in rural Missouri, nineteen-year-old Katie Lenz was hit by a drunk driver.  Rescuers' attempts to extricate her from the mangled car weren't working; paramedics began to fear for her life.  

Katie asked her rescuers to stop working and pray.  At that moment, a Catholic priest appeared.  He prayed with them.  After Katie was rescued, those working at the site turned to thank him, but the priest was gone.  Traffic had been blocked off for a quarter mile; no other cars or people were visible.

Was he an angel?

Update: Strangely, the priest doesn't appear in any of the more-than-70 photos of the accident site.