President Joe Biden prepared to address the nation Tuesday night shortly after returning to the White House from a five-day trip to Asia that was bookended by “horrific” mass tragedy.

Biden was on Air Force One Tuesday afternoon when officials said a gunman acting alone killed at least 14 students and a teacher at a Texas elementary school. His departure for Asia last week came just two days after he met with victims’ families after a hate-motivated shooter killed 10 Black people at a grocery store in Buffalo, New York. The back-to-back tragedies served as sobering reminders of the frequency and brutality of an American epidemic of mass gun violence.

Biden directed that American flags be flown at half-staff through sunset Saturday in honor of the victims.

Vice President Kamala Harris said that people normally say in a moment like this, “our hearts break — but our hearts keep getting broken … and our broken hearts are nothing compared to the broken hearts of those families.”

“We have to have the courage to take action … to ensure something like this never happens again,” she said.

White House press secretary Karine Jean-Pierre said Biden was briefed on the shooting by deputy chief of staff Jen O’Malley-Dillon and other members of his senior team aboard Air Force One.

Shortly before landing in Washington, Biden spoke with Texas Gov. Greg Abbott from the presidential plane “to offer any and all assistance he needs in the wake of the horrific shooting in Uvalde, TX,” White House communications director Kate Bedingfield tweeted.