President Barack Obama said it's absolutely imperative that authorities investigate the death of Trayvon Martin as thoroughly as possible and expressed sympathy for the Florida teenager's parents.

 My main message is to the parents, Obama said. If I had a son, he'd look like Trayvon. I think they are right to expect that all of us as Americans are going to take this with the seriousness it deserves.

The comments came during a news conference at which Obama announced his nomination of Jim Yong Kim to head the World Bank.

Trayvon was an unarmed high school student who was shot and killed by George Zimmerman in the suburbs outside Orlando, Fla., on Feb. 26 while walking home from a convenience store. The case has drawn heated anger over the fact Zimmerman, who claims he acted in self-defense, hasn't been arrested or prosecuted for the shooting.

Zimmerman is a white Hispanic; Trayvon was black. The case has sparked complaints of racism or racial motivation in the shooting and its handling by local police in Sanford, Fla.

Obama said he didn't want to impair any investigation that's taking place right now with his statement, but he was glad the Justice Department is looking into the case and that Florida has set up a task force to investigate.

Obviously, this is a tragedy, the president said. I can only imagine what these parents are going through. And when I think about this boy, I think about my own kids. I think every parent in America should be able to understand why it is absolutely imperative we investigate every aspect of this.

I think of us have to do some soul-searching to figure out how something like this happened.

Presidential candidate Newt Gingrich, one of Obama's Republican rivals, also commented on the case. On CNN Thursday, the former House of Representatives speaker said he thought the local district attorney was doing the right thing by submitting evidence to a grand jury.

I think that Americans can recognize that while this is a tragedy, and it is a tragedy, we're going to relentlessly seek justice. And I think that's the right thing to do, Gingrich said.

Two other Republican presidential hopefuls, Rick Santorum and Mitt Romney, responded to questions about Trayvon after Obama's statement. According to Buzzfeed, Santorum called the teen's death horrible, chilling while Romney said it was a tragedy that requires thorough investigation that reassures the public that justice is carried out with impartiality and integrity.