Texas school shooting: Suspect's grandmother upgraded to good condition

President Joe Biden and first lady Jill Biden will be traveling to Texas in the "upcoming days," the president said Wednesday.

The two plan to meet with the victims' families "and let them know that we have a sense, just a sense of their pain. And hopefully bring some little comfort to the community in shock and grief and in trauma," the president said during an address Wednesday afternoon.

The president said he was "sick and tired" of the "carnage" that is happening in the U.S.

"The idea that an 18-year-old can walk into a store and buy weapons of war, designed and marketed to kill, is I think just wrong. Just violates common sense," he said. "Where's the backbone, where's the courage to stand up to a very powerful lobby?"

The accused gunman in Tuesday's deadly school shooting purchased two AR-15-style rifles at Oasis Outback, a federally licensed store located in Uvalde, law enforcement sources told ABC News.

A general manager at Oasis Outback told ABC News that he is working with law enforcement but would not comment on whether the alleged shooter did or did not purchase his guns there.

Oasis Outback is located approximately 3 miles from Robb Elementary School.

According to the Bureau of Alcohol, Tobacco, Firearms and Explosives, the alleged shooter made his gun purchases on two separate days: May 17 and May 20. That means he bought the first AR-15-style rifle one day after he turned 18 and the second four days before the shooting.

Both weapons were purchased at that same store, Steve McCraw, the director of the Texas Department of Public Safety, confirmed during a press conference Wednesday afternoon.

The guns were purchased legally.

-ABC News' Josh Margolin, Aaron Katersky, Laura Romero and Olivia Rubin

The House will move on a bill to create a national red flag law, according to House Majority Leader Steny Hoyer, D-Maryland.

The bill would allow family members or law enforcement officers to "petition for an extreme risk protection order with respect to an individual who poses a risk to themselves or others."

The bill is sponsored by Rep. Lucy McBath, D-Ga., whose 17-year-old son Jordan Davis was fatally shot in 2012.

Hoyer said on Twitter Wednesday that he plans to bring the bill to the floor when the House returns from recess next month.

-ABC News' Lalee Ibssa

The gunman warned about the shooting in private messages on Facebook minutes beforehand, a spokesperson for Meta said Wednesday. The warning on Facebook was made in "private one-to-one text messages that were discovered after the terrible tragedy occurred."

The gunman sent three messages on Facebook about 30 minutes before the shooting saying: "I'm going to shoot my grandmother," "I shot my grandmother" and "I'm going to shoot an elementary school," Texas Gov. Greg Abbott said at a press conference.

Abbott said the suspect was reportedly a high school dropout. Officials have reportedly not identified a criminal history for the suspect, but Abbott said he may have had a juvenile record, but that is yet to be determined.

Abbott said the suspect did not have a known mental health history.

According to the ATF, the shooter made his gun purchases on two separate days: May 17 and May 20.