ANACORTES, Wash. (AP) — Two BNSF trains derailed in separate incidents in Arizona and Washington state on Thursday, with the latter spilling diesel fuel on tribal land along Puget Sound.

No injuries were reported. It wasn’t clear what caused either derailment.

The derailment in Washington occurred on a berm along Padilla Bay, on the Swinomish tribal reservation near Anacortes. Most of 5,000 gallons (nearly 19,000 liters) of spilled diesel fuel leaked on the land side of the berm rather than toward the water, according to the state Ecology Department.

Officials said there were no indications the spill reached the water or affected any wildlife.

Responders placed a boom along the shoreline as a precaution and removed the remaining fuel from two locomotives that derailed. Four tank cars remained upright.

The derailment in western Arizona, near the state’s border with California and Nevada, involved a train carrying corn syrup. A spokeswoman for the Mohave County Sheriff’s Office, Anita Mortensen, said that she was not aware of any spills or leaks.

BNSF spokeswoman Lena Kent said an estimated eight cars derailed in Arizona and were blocking the main track. The cause of the derailment was under investigation, and it was not immediately known when the track will reopen.

The derailments came Alabama and other states.

The U.S. averages about three train derailments per day, according to federal data, but relatively few create disasters.

Last month, a freight train carrying hazardous chemicals derailed in East Palestine, Ohio, near the Pennsylvania border, igniting a fire and causing hundreds of people to be evacuated.

Officials seeking to avoid an uncontrolled blast intentionally released and burned toxic vinyl chloride from five rail cars, sending flames and black smoke high into the sky. That left people questioning the potential health impacts even as authorities maintained they were doing their best to protect people.