An 18-year-old has been identified as the gunman who stormed into a Texas primary school and murdered at least 19 children and two teachers.
Salvador Ramos was “the quiet type” who hinted on social media about an attack and purchased two assault weapons after he turned 18.
It is the latest mass gun killing in the US and the worst school shooting in nearly a decade.
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The mass shooting began when the suspect shot his own grandmother, who survived, according to authorities.
He then crashed his car near the Robb Elementary School in Uvalde, Texas – a town around 80 miles (130km) west of San Antonio, before launching a bloody rampage which ended with him being shot by police.
Governor Greg Abbott said Ramos had been a student at Uvalde High School and a resident of the community of some 16,000 people.
There, he launched a bloody rampage that ended with him being shot dead by police. The motive was not immediately clear.
In a bid to find a motive for the horrific attack, police are studying his two social media accounts.
The teenage gunman had hinted on social media that an attack could be coming, according to state senator Roland Gutierrez, citing state police.
He noted that Ramos, who he said was born in North Dakota, had bought two “assault weapons” after turning 18.
Before heading to the school, Ramos opened fire at his grandmother with two military-style rifles he purchased on his birthday, Sen Gutierrez said.
“That was the first thing he did on his 18th birthday,” he said.
US President Joe Biden later said: “The idea that an 18-year-old kid can buy assault weapons is wrong.”
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The grandmother was then airlifted to hospital and had survived the shooting, officials said, though her condition was not known.
Investigating police believe the gunman posted photos on Instagram of two guns he used in the shooting.
Officers were also examining whether he made statements online alluding to the attack in the hours before the assault, a law enforcement official said.
The official added that police had served multiple search warrants on Tuesday night and gathered telephone and other records.
They were also attempting to contact Ramos’ relatives and were tracing the firearms.
Suspect posed with guns and worked at fast-food chain
Police say Ramos acted alone in the act and is believed to have abandoned his car outside the school.
Officers tried to engage the suspect, clad in body armour, before he entered the school grounds with a handgun and possibly a rifle.
Photos on his social media show him posing with what appears to be a semi-automatic weapon.
Days before the attack, photos believed to be posted by Ramos on Instagram include what appeared to be a Daniel Defense AR-15 with a high-capacity magazine. Another image from 28 April showed someone holding a magazine.
According to CNN, Ramos texted photos to a former classmate of a firearm and a bag full of ammunition days before the attack.
“He would message me here and there, and four days ago he sent me a picture of the AR he was using… and a backpack full of 5.56 rounds, probably like seven mags,” the former classmate said.
“I was like, ‘Bro, why do you have this?’ and he was like, ‘Don’t worry about it’,” the student said. “He proceeded to text me, ‘I look very different now. You wouldn’t recognise me’.”
The Daily Dot reported that one of Ramos’ friends on Instagram shared a screenshot that Ramos had sent showing a receipt for a gun he bought from Daniel Defense, a gun manufacturer.
Another former classmate, who asked not to be identified, told CNN that he and Ramos were somewhat “close” and used to play Xbox together.
He added that Ramos was a fan of the shooting and combat game Call of Duty.
‘Quiet type’ with an aggressive streak
Meanwhile, a manager at the local Wendy’s – a major fast-food chain in the US – said that Ramos worked the day shift at the restaurant.
“He felt like the quiet type, the one who doesn’t say much. He didn’t really socialise with the other employees,” Wendy’s evening manager Adrian Mendes said.
But one young woman, a former Wendy’s colleague, detected an aggressive streak, the Daily Beast reports.
“He would be very rude towards the girls sometimes, and one of the cooks, threatening them by asking, ‘Do you know who I am?’ And he would also send inappropriate texts to the ladies,” said the former co-worker, who wanted to remain anonymous.
“At the park, there’d be videos of him trying to fight people with boxing gloves. He’d take them around with him.”
The Wendy’s co-worker added that Ramos did not seem to socialise much outside his clique of friends – a group she described as “emo” or “alternative.”
The tragedy in Uvalde on Tuesday marks the deadliest school shooting in Texas history, adding to a grim tally of mass shootings in the state that have been among the deadliest in the US over the past five years.