TEMPE, AZ (3TV/CBS 5) – Just two weeks after a train derailment and bridge collapse caused a massive fire in Tempe, trains are rolling once again.

An Arizona’s Family photographer was there when the first train crossed the bridge on the newly laid rails overnight.

Investigators working to find cause of train derailment, bridge collapse in Tempe

The July 29 derailment, which dominated Arizona’s news and made national headlines, was the second one in less than a month. While the June 26 derailment was relatively minor and went largely unnoticed, the plume of thick black smoke from the July 29 fire was visible for miles.

Early that morning, as many as 10 cars derailed, according to a spokesman for Union Pacific Railroad. The south side of the bridge – where Tempe Beach Park is located -- collapsed and caught fire. Nobody was hurt, but one person in the park was treated for smoke inhalation.

ASU engineers look at possible reasons for Tempe rail bridge collapse

The Salt River Union Pacific Bridge, which runs parallel to the Mill Avenue Bridge, was built in 1912 and survived floods that destroyed three other truss bridges in the same location.

Union Pacific is responsible for the bridge and its upkeep. It says bridges are visually inspected every 30 days. The Salt River Bridge had its annual inspection on July 9.

Union Pacific: Inspection showed railway bridge 'in good standing' before Tempe derailment

The cause of the train derailment, bridge collapse and subsequent fire is under investigation.