Spain is beginning three days of mourning after at least 68 people were killed and dozens more were injured in one of the worst rail disasters in Europe’s modern history, the BBC reports. Emergency crews worked through the night under powerful floodlights to cut open metal carriages in the search for victims, with many of those killed in the crash still to be identified. Officials are investigating the cause of the disaster, which occurred when a train travelling from Madrid to Seville barrelled into a stationary train on Wednesday morning. Prime Minister Pedro Sánchez said the “whole of Spain is grieving”, adding that “lives have been shattered, families have been torn apart, the pain is immense”. Hundreds of personnel have been deployed to the disaster site to assist with recovery efforts, according to Spain’s interior ministry, with drones and helicopters being used to find victims and remove rubble.