Around the mid-point of the game you will come across an open area, with a guard crawling towards a med-kit, after a moment a doctor from the building on the other side of the area comes to the help of the guard, and ends up being shot by the sniper.
I saved them both by shooting the grill where the sniper is with a rocket launcher, the sniper died.
I’m reporting this as a bug since I believe we shouldn’t be able to kill the sniper.
There was no dialogue with the doctor, pressing E on him just made him turn his head a little and then back. Saying nothing and just staying there.