Two more people have died from Saturday's mass shooting at a Walmart in El Paso, Texas, raising the death toll in that attack to 22, authorities said. El Paso police said both victims died Monday.

The police department said on Twitter one victim died early Monday morning at a hospital and another died just after 10 a.m. More than two dozen people were wounded in the attack.

The suspected gunman, 21-year-old Patrick Crusius, has been booked on capital murder charges and is being held without bond, according to the El Paso County District Attorney's Office. A law enforcement source said investigators were piecing together a timeline of Crusius' movements, CBS News senior investigative producer Pat Milton reports.

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Investigators were tracing Crusius' route to El Paso from Allen, Texas, where he lives, Milton reports. It is about a ten-hour drive away. Authorities were looking into where Crusius stopped for gas and food, whether anyone may have seen him along the way and if he spoke to anyone.

Authorities were investigating whether Crusius acted alone, Milton reports. That was one of the statements Crusius has allegedly made to investigators.

In a racist manifesto Crusius allegedly wrote, he expressed support for the Christchurch, New Zealand, shooter and denounced the increasing Hispanic population in Texas. Speaking from the White House on Monday, President Trump condemned the El Paso mass shooting and another hours later in Dayton, Ohio, in his first public remarks since the attacks.