At least two people died and several were injured when a building in a central Madrid belonging to the Catholic Church collapsed on Wednesday after an explosion, Mayor Jose Luis Martinez-Almeida told reporters.
Initial investigations suggested that the blast in Calle de Toledo, a street leading out from the city centre, had been caused by a gas leak, he said.
Smoke billowed out of the collapsed building and rescue workers evacuated elderly people from a nearby nursing home.
A Church official said one church volunteer was missing.
The building was a complex that provided residential training for priests and also gave meals to homeless people, a neighbour said.