DENVER Police in Denver are investigating a fatal crash involving a pedestrian and a train on RTDs A Line Monday.A Line service to and from Denver International Airport has been disrupted.It happened around 3:30 p.m. at the Quebec Street-Smith Road crossing.Police said a pedestrian, an adult male, was killed after they were struck by a passing train.Details of the incident are not known at this time.RTD is running shuttle buses on the route between the 38th/Blake Station and the 40th/Airport-Gateway Park Station.