>went to baggage claim, removed gun from suitcase and killed several - then just surrendered
That sounds remarkably similar to what happened in Finland with the murder of Tiina Wilén-Jäppinen, a local politician, and two other women.
English link:
https:// www.theguardian.com/world/2016/dec/04/three-women-shot-dead-outside-restaurant-finland
The article doesn't mention that Wilén-Jäppinen had just come out from a restaurant where she had been with two journalists, the other two victims, being interviewed about… something. The Finnish media never bothered to dig and never questioned the idea that the murders had been caused by a random nut wanting to murder some people at random.