Three cows that wandered onto railroad tracks triggered the derailment of an overnight train heading from Lisbon to Madrid and caused major disruption for passengers, Portuguese rail operator Refer said.
The train, which was carrying 45 people, partially came off the tracks at around 1:45am local time near Castelo de Vide, around 125 miles northeast of Lisbon and close to the border with Spain.
The incident, in which no one was injured, was caused by three cows that wandered onto the line, a Refer spokesman told Portugal's TSF radio station.
Passengers heading to Madrid were able to complete their journey by boarding a train coming in the opposite direction that had to return to the Spanish capital, though passengers headed to Lisbon were forced to complete their journey by road.
According to the Refer spokesman, the line should be fully reopened by the end of the day after repair work by Spanish technicians.