Updated Aug.4, 2:10PM

In 13 hours of carnage in the United States, two shooters in separate incidents killed 29 people and injured dozens, leaving authorities searching for motives behind the mayhem.

A gunman wearing body armor and carrying extra magazines of ammunition was shot to death by police less than a minute after he opened fire early Sunday in a popular nightlife area in the Midwest city of Dayton, Ohio. The man killed nine people including his own sister and injured at least 27, four of them seriously.

Police said they believe there was only one shooter in the incident, but have yet to suggest a motive. News accounts identified the shooter as 24-year-old Connor Betts, who identifies himself on social media as a psychology student at a community college in the Dayton area.

Dayton Mayor Nan Whaley said the quick response by police “saved literally hundreds of lives” in the crowded Oregon district of the city filled with bars, restaurants and theaters.

She said the gunman was carrying a .223-caliber semi-automatic weapon, the same-sized weapon a gunman employed in the one of the most horrific mass shootings in the U.S. in recent years, the assault in which 20 school children and six adults were killed in Newtown, Connecticut in 2012.

The Ohio bloodshed occurred about 13 hours after police in the U.S.-Mexican border city of El Paso, Texas, say a gunman opened fired at a Walmart store, killing at least 20 people and wounding 26 — an attack authorities say they are investigating as a possible hate crime targeting Hispanics.

The El Paso and Dayton incidents are the nation’s 21st and 22nd mass killing incidents this year, according to a database compiled by the Associated Press, USA Today and Northeastern University. The archive defines a mass killing as four or more people shot dead, excluding the gunman, at one location. A separate database counts more than 250 incidents this year in which four or more people have been killed or wounded.

The latest incidents occurred a week after a gunman killed three at a food festival in California and followed the killing of 58 at a country music festival in 2017 in California, 49 at an Orlando, Fla., night club in 2016 and 25 at a Texas church in 2017.

U.S. authorities occasionally try to figure out ways to stop the slaughter of innocents in a country where gun ownership is enshrined as a constitutional right. Some lawmakers have attempted to curb gun ownership or stiffen the regulations surrounding gun sales, but have generally been rebuffed by other lawmakers opposed to new restrictions.

After the Dayton attack, Ohio Sen. Sherrod Brown said he was angered that state and national lawmakers won’t approve more gun controls, saying politicians’ “thoughts and prayers are not enough” of a response to mass killings.

U.S. President Donald Trump said Sunday on Twitter, “The FBI, local and state law enforcement are working together in El Paso and in Dayton, Ohio. Information is rapidly being accumulated in Dayton. Much has already be learned in El Paso. Law enforcement was very rapid in both instances. Updates will be given throughout the day!”

The FBI, local and state law enforcement are working together in El Paso and in Dayton, Ohio. Information is rapidly being accumulated in Dayton. Much has already be learned in El Paso. Law enforcement was very rapid in both instances. Updates will be given throughout the day!

— Donald J. Trump (@realDonaldTrump) August 4, 2019

“God bless the people of El Paso Texas. God bless the people of Dayton, Ohio,” he implored.

God bless the people of El Paso Texas. God bless the people of Dayton, Ohio.

— Donald J. Trump (@realDonaldTrump) August 4, 2019

Several Democratic presidential candidates — Sens. Cory Booker and Bernie Sanders and former Texas Congressman Beto O’Rourke — blamed Trump’s anti-immigrant rhetoric for fostering a climate of hate leading to the El Paso shooting.

 “Donald Trump is responsible for this,” Booker told CNN. “He is responsible because he is stoking fears and hatred and bigotry.”

But acting White House chief of staff Mick Mulvaney rejected any attempt to blame Trump.

“I blame the people who are sick,” Mulvaney told NBC’s Meet the Press interview show. “People are going to hear what they want to hear,” but added: “This was a political motive by a crazy person.”

In El Paso, police chief Greg Allen said police are seeking to confirm that the 21-year-old white male suspect now in custody was the author of an online posting predicting a shooting spree intended to target Hispanics.

The suspect was identified by police as Patrick Crusius, who lived in the Dallas area, hundreds of kilometers away from El Paso.

The post appeared online about an hour before the shooting and included language that complained about the “Hispanic invasion” of Texas. The author of the manifesto wrote that he expected to be killed during the attack.

The writer of the manifesto denied that he was a white supremacist, but decried “race mixing” in the United States, calling instead for territorial enclaves separated by race. The first sentence of the document expressed support for the man accused of killing 51 people at two mosques in Christchurch, New Zealand, in March, after he had posted his own conspiracy theory that non-white migrants were replacing whites.

Congressman Joaquin Castro of Texas said in a statement that in El Paso, “This vile act of terrorism against Hispanic Americans was inspired by divisive racial and ethnic rhetoric and enabled by weapons of war. The language in the shooter’s manifesto is consistent with President Donald Trump’s description of Hispanic immigrants as ‘invaders.'”

Castro, chairman of the Congressional Hispanic Caucus, said, “Today’s shooting is a stark reminder of the dangers of such rhetoric.”

Mexican President Andres Manuel Lopez Obrador said three Mexicans were killed in the shooting and six Mexicans were wounded.
 
Trump said Saturday that he and first lady Melania Trump “send our heartfelt thoughts and prayers to the great people of Texas.”

He also tweeted: “Today’s shooting in El Paso, Texas was not only tragic, it was an act of cowardice.  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 began receiving calls about 10:39 a.m. local time with multiple reports of a shooting at Walmart and the nearby Cielo Vista Mall complex on the east side of the city.

 
Sgt. Robert Gomez, a spokesman with the El Paso Police Department, said most of the shootings occurred at the Walmart, where there were more than 1,000 shoppers and 100 employees. Many families were taking advantage of a sales-tax holiday to shop for back-to-school supplies, officials said.
 
“This is unprecedented in El Paso,” Gomez said of the mass shooting.
 
Gomez said an assault-style rifle was used in the shooting.

El Paso, a city of about 680,000 people in western Texas, shares the border with Juarez, Mexico.

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