WATCH: Doocy grills new press secretary over Biden visiting Buffalo but not Waukesha

"How come the President is visiting Buffalo after a senseless tragedy there, but he couldn't visit Waukesha after 6 were killed and 61 injured in an attack on a Christmas parade there?"

Jean-Pierre responded, "He's been to many communities. Buffalo, he's able to go tomorrow to Buffalo before the trip. That is something that was important for him to do, but he has visited many other communities. Buffalo is not the first community, sadly, that he has had to go to because of a violent attack."

In remarks on Sunday, Biden said: "I wanted to say a word about yesterday's mass shooting in Buffalo, New York. A lone gunman, armed with weapons of war and a hate-filled soul, shot and killed ten people in cold blood at a grocery store on Saturday afternoon. Jill and I, like all of you, are praying for the victims and their families, and a devastated community.

"I've been receiving updates from my team in the White House, that's in close contact with the Justice Department. We're still gathering the facts. Already, the Justice Department has stated publicly that is investigating the matter, as a hate crime, racially motivated act of white supremacy and violent extremism.

"As they do, we must all work together to address the hate remains a stain on the soul of America. Hearts are heavy once again, but our resolve must never ever waver. No one understands us more than the people sitting in front of me. Moms, dads, children, family members, about how those folks in Buffalo feel today, when they got the call.

"They were pulled into, it's as if you got pulled into a black hole in your chest. There's no way out, Jill and I know. We know no memorial, no gestures can fill the void in the hearts they have now or that you, you who've lost someone feels as well," Biden said.

Biden's Twitter account reported that Biden and First Lady Jill would be visiting Buffalo on Tuesday.

Brooks has been charged with the Waukesha massacre, which took place when he allegedly plowed his car into a Christmas parade. The attack took place just days after a not guilty verdict was returned in the case of Kyle Rittenhouse.

Saturday's massacre in Buffalo was allegedly committed by an 18-year-old who, with racist intentions, shot 10 black shoppers to death at a Tops grocery store. Police have the suspect in custody. He is currently in solitary confinement and on suicide watch.

Brooks pleaded not guilty to all charges. Victims of the attack include an 8-year-old boy along with members of the Dancing Grannies troupe that were performing in the parade.