The entire nation was now aroused, and many wanted to go to war with Spain immediately. But the Spaniards professed to be ignorant of the cause of the explosion, and said it must have come from the _inside_ of the ship and not the _outside_. Without delay a Board of Inquiry was established, and it was settled that the explosion had come from the outside, probably from a mine set by the Spaniards in Havana Harbor.