Monday’s deadly Amtrak train derailment may have been caused by the train striking something on the railway, according to an unconfirmed Associated Press report.

A preliminary investigation suggests maintenance problems are unlikely to blame because the incident took place on brand-new tracks, a government official told the AP on condition of anonymity.

At least three people were killed and the death toll is expected to rise, the Associated Press reported.

The Amtrak 501 plunged off an overpass onto I-5 near Lacey, Washington, sometime before 7:45 a.m., during its inaugural run between Seattle, Washington, and Portland, Oregon.

During an afternoon briefing on his national security strategy, President Trump expressed “our deepest sympathies and most heartfelt prayers for the victims,” adding: “We are closely monitoring the situation and coordinating with local authorities.”