Democratic presidential candidate Beto O'Rourke will introduce Khalid at the R&B singer's benefit concert Sunday in El Paso for the families affected by the mass shooting at Walmart.

The former congressman will introduce Khalid and speak at the singer's A Night for Suncity concert, which already has sold out.

More:Khalid's 'A Night for Suncity' benefit concert for El Paso shooting victims sells out

Khalid, an Americas High School graduate, announced the concert in the days after the Aug. 3 shooting in which 22 people were killed and 25 were injured by a white gunman at an East Side Walmart near Cielo Vista Mall.

More:El Paso shooting: Khalid plans August benefit concert for Walmart victims, families

"Over the past few days, my mind and heart have been heavy," Khalid said in a tweet in the days after the shooting. "Hearing/seeing an act of terrorism happen so close to home, my family, and my friends has been unbelievable and shocking."

The concert will be at the Don Haskins Center. Doors open at 6 p.m. and O'Rourke will speak at 7:50 p.m.

After the shooting, O'Rourke left the campaign trial to return to his hometown. He resumed campaigning after remaining in El Paso for nearly two weeks. This is O'Rourke's first public event in El Paso since.

Eleanor Dearman covers the Texas Capitol and politics for the USA TODAY Network Austin Bureau and the El Paso Times. She may be reached at 361-244-0047; edearman@elpasotimes.com; @EllyDearman on Twitter.