A portion of the Salt River Union Pacific Railroad Bridge, which stretches over Tempe Town Lake, has collapsed, and the train on the bridge was on fire. Debris was in the water next to the park.
More than 90 firefighters were on the scene, where thick smoke filled the air and planes from nearby Phoenix Sky Harbor International Airport were being diverted.
Tempe police Chief Sylvia Moir tweeted that there were "no injuries known at this time but the scene is very dangerous. Stay out of Tempe Town Lake and away from the area."