"Like all Americans, I am horrified and heartbroken by the tragedy that has stricken Boston and its Boston Marathon this afternoon.
"The investigation into these terrible explosions has only just begun. As we await further details into who or what is behind these explosions, I ask that my fellow Arizonans join me in praying for Boston. From the participants to the spectators, from the first responders to the families -- let our hearts be with them as they put together the pieces following this tragic day.
"If these explosions were an intentional act, I am confident those responsible will be brought to justice. We can trust that the full weight of local, state and federal law enforcement has been brought to bear as part of this investigation. For now, let us rally together as a Nation and stand with the people of Massachusetts and the City of Boston. May our prayers give them strength."