President Barack Obama delivered a brief statement on the Boston Marathon bombing Tuesday morning, in which he derided the attack as “heinous and cowardly,” and informed the American people that the FBI is investigating it as an act of terror.

“This was a heinous and cowardly act, and given what we now know about what took place, the FBI is investigating it as an act of terrorism,” the president said from the podium in the White House briefing room. “Any time bombs are used to target innocent civilians, it is an act of terror.”

This represents a shift from Obama’s Monday evening statement on the attack, in which the president declined to use the term “terrorism” in the immediate aftermath of the attack.

Acknowledging that the investigation is still in its very early stages, the president said “what we don’t yet know is who carried out this attack or why — whether it was planned and executed by a terrorist organization, foreign or domestic, or was the act of a malevolent individual.”

“It will take time to follow every lead and determine what happened, but we will find out,” Obama continued. “We will find whoever harmed our citizens, and we will bring them to justice.”

“We also know this: The American people refuse to be terrorized,” the president said. “Because what we saw in the aftermath of the explosions were stories of heroism and kindness and generosity and love.”

“If you want to know who we are, what America is, how we respond to evil, that’s it,” Obama added. “Selflessly, compassionately, unafraid.”

Obama concluded by promising to disclose future details as they become available.

Video of President Obama’s statement is below:

AP Photo/Susan Walsh