Spain opened an investigation into the theft of copper signaling cables on the high-speed line between Madrid and Andalusia.
The crime affected thousands of commuters, leaving many stranded in trains or at railway stations overnight just a week after similar scenes during a nationwide power blackout. It also sparked a political quarrel.
What do we know about the cable thefts?
Thieves took cables from five points along a roughly 10-kilometer (about 6-mile) stretch of rail line in what Transport Minister Oscar Puente described as a "serious act of sabotage" in a post on X.
"If anyone can offer information, any assistance is appreciated," said Puente. "These incidents are very serious."
The minister said the thieves had gained access to the cable via forest trails between olive trees.
State-owned national rail infrastructure operator Adif said high-speed services had been restored between Madrid-Toledo and Madrid-Andalusia — both out of Madrid and from the southern stations in Seville, Malaga, and Granada. It said that traffic would return to normal throughout the course of Monday.
How were passengers affected?
The theft meant that thousands of people were left waiting in Madrid's Atocha station, with nine trains stranded between stations and many passengers forced to spend the night onboard.
The latest disruption followed a long weekend in Madrid and ahead of the Andalusian capital Seville's famous Feria festival.
Hundreds of passengers were also left stuck on trains last week amid a nationwide blackout that hit Spain and neighboring Portugal.
Spain's high-speed rail network — which connects almost all the country's big cities — has quickly expanded as part of a government push to decarbonize public transport.
How have Spain's politicians reacted?
The center-right opposition Popular Party (PP) demanded that the government conduct an audit of the rail network and probe the constant incidents being reported.
The opposition party requested compensation for all travelers affected by the delays that occurred this Sunday.
"What happened today, I repeat, is not an exception; it is the new normal for a government that is overwhelmed," said Juan Bravo, the PP's Deputy Secretary for the Economy, in a press conference.
PP leader Alberto Nunez Feijoo said the railway incidents offered "images unbecoming of the euro's fourth largest economy."
In turn, the ruling PSOE described Feijoo as a "political scavenger" for using the incident to attack the government rather than condemning the sabotage of the rail lines.