Strong Explosion Rocks Building In Central Madrid Strong Explosion Rocks Building In Central Madrid "Nine fire crews and 11 ambulances have gone to Calle Toledo following an explosion in a building," local emergency services tweeted. The cause of the blast was not immediately clear. Madrid: A strong explosion rocked a building in central Madrid on Wednesday, witnesses said, with images from Spanish television and the emergency services showing the street covered in debris. "Nine fire crews and 11 ambulances have gone to Calle Toledo following an explosion in a building," local emergency services tweeted. Promoted The cause of the blast was not immediately clear.