French police officers patrol at the Human Rights Square, near the Eiffel Tower, Paris, Tuesday April 16, 2013. In the wake of the Boston attacks, the French Interior Ministry has ordered local authorities across France to immediately reinforce security measures already in place since the January intervention in Mali began. The ministry did not change the threat level. (AP Photo/Remy de la Mauviniere)
World responds to Boston bombing
In the wake of the Boston attacks, several countries, including France and Great Britain, have ordered local authorities to step up security and reinforce measures already in place.