Thousands of rail passengers in Spain were hit with delays after copper¹ cables used in the signaling system of a high-speed line traveling south from Madrid to Seville were stolen at five locations.|

The theft, which happened late Sunday, affected² dozens of trains traveling between Madrid and the southern Andalusian cities of Seville, Malaga and Granada as many people were returning home to Spain’s capital after a holiday weekend.

Copper prices are high on global markets, meaning criminals stand to collect big sums of cash from selling the material.

Droves of travelers crowded Madrid’s Atocha station Monday seeking information about their trains from rail employees and screens with updated departure times.

The incident came a week after a massive power outage in Spain and Portugal ground high-speed train traffic in Spain to a halt, stranding³ thousands of passengers for several hours.