AC759: "Tower, just want to confirm. This is Air Canada 759. We see lights on the runway there. Across the runway. Can you confirm are we cleared to land?"
SFO TOWER: "Confirmed cleared to land. Runway 28 Right. There's no one on 2-8 Right but you."
I wonder why the tower just nonchalantly said there's nothing there if a crew reports seeing unexpected lights. How did they know a runway incursion, even by a vehicle, had not taken place ?
It's the old adage "If it doesn't look right, assume it's wrong".