Police and FBI investigators in Texas searched for clues on Sunday to explain what drove a young gunman from the Dallas area to kill 20 people at a Walmart store hundreds of miles away in the border city of El Paso.
Texas Governor Greg Abbott said Saturday morning's rampage appeared to be a hate crime, and police cited a "manifesto" they attributed to the suspect as evidence that the bloodshed was racially motivated.
The shooting immediately reverberated on the U.S. presidential campaign trail, with several Democratic candidates denouncing the rise of gun violence and repeating calls for tighter gun control measures.
At least two candidates, Mayor Pete Buttigieg of South Bend, Indiana, and El Paso native Beto O'Rourke, a former congressman, drew connections to a resurgence in white nationalism and xenophobic politics in the United States.
"America is under attack from homegrown white nationalist terrorism," Buttigieg said at a candidates forum in Las Vegas.
On Twitter, U.S. President Donald Trump branded the shooting "an act of cowardice," adding, "I know that I stand with everyone in this country to condemn today's hateful act. There are no reasons or excuses that will ever justify killing innocent people."
Police said the suspect opened fire with a rifle on shoppers, many of them bargain-hunting for back-to-school supplies, then surrendered to officers who confronted him outside the store.
The massacre came just six days after the last major outbreak of U.S. gun violence in a public place - a food festival in California where a teenager killed three people with an assault rifle and injured a dozen others before taking his own life in a hail of police gunfire.
Police said the suspect in Saturday's shooting was a 21-year-old white male from Allen, Texas, a Dallas suburb some 650 miles (1,046 km) east of El Paso, which lies along the Rio Grande across the U.S.-Mexico border from Ciudad Juarez.
Multiple news media outlets, citing law enforcement officials, named the accused assailant as Patrick Crusius.
In a briefing for reporters on Saturday night, some 12 hours after the shooting, an El Paso police spokesman, Sergeant Robert Gomez, said police were interviewing the suspect, while investigators continued to collect evidence at the crime scene.
(Graphic: Mass shootings in the United States - https://tmsnrt.rs/2KefvTT)
SIGNS OF HATE
Several local politicians said the gunman was an outsider, suggesting he had traveled hundreds of miles from the Dallas area to commit mass murder. But Gomez declined to say how long the suspect might have been in El Paso before the shooting.
Authorities did not offer a precise motive. However, El Paso Police Chief Greg Allen said investigators were examining a "manifesto" from the suspect indicating "there is a potential nexus to a hate crime."
A four-page statement posted on 8chan, an online message board often used by extremists, and believed to have been written by the suspect, called the Walmart attack "a response to the Hispanic invasion of Texas."
It also expressed for support for the gunman who killed 51 people at two mosques in Christchurch, New Zealand, in March.
CNN reported the FBI had opened a domestic terror investigation into the Texas shooting.
"We are going to aggressively prosecute it both as capital murder but also as a hate crime, which is exactly what it appears to be," Texas Governor Abbott told reporters.
El Paso and Ciudad Juarez, together with the neighboring city of Las Cruces, New Mexico, form a metropolitan border area of some 2.5 million residents constituting the largest bilingual, bi-national population in North America.
Mexico's President Andres Manuel Lopez Obrador said three Mexican nationals were among the 20 people killed in the shooting, and six others were among 26 victims who were wounded.
The carnage ranked as the eighth-deadliest mass shooting in modern U.S. history, after a 1984 shooting in San Ysidro, California, that claimed 21 lives.
Gomez said investigators were still determining the sequence of events. But video clips from the scene showed victims lying on the ground inside and outside the store. One shopper told Reuters the gunshots sounded like they began outside the building and then moved inside.
El Paso Mayor Dee Margo said police responded to the shooting within six minutes.
Local television station KTSM-TV published two photos it cited a law enforcement source as saying were security-camera images of the suspect as he entered the Walmart, wearing eyeglasses, khaki trousers and a dark T-shirt, and wielding an assault-style rifle. He appeared to be wearing headphones or ear protection.
Eyewitnesses described scenes of pandemonium as shoppers fled for their lives, including Kianna Long who was at the Walmart with her husband when they heard gunfire.
The couple sprinted through a stock room at the back of the store before huddling with other customers in a shipping area, she recounted.
"People were panicking and running," Long said. "They were running close to the floor, people were dropping on the floor."
(Reporting by Julio-Cesar Chavez in El Paso; Additional reporting by Alex Dobuzinskis and Steve Gorman in Los Angeles, Tim Reid in Las Vegas and Daniel Wallis in New York; Writing by Steve Gorman; Editing by Jane Merriman)