At least 15 people were killed and 18 others injured on Wednesday when a mountain tram derailed in a tourist district of Portugal’s capital, Lisbon, according to emergency services official Tiago Augusto.

All victims were transported to nearby hospitals, with officials confirming that foreigners were among the injured, though their nationalities were not disclosed.

The Portuguese government declared a national day of mourning on Thursday to honor the victims.

Footage from the scene showed the tram completely destroyed, as emergency teams worked to pull passengers from the wreckage.