Did the police in Texas delay their response at the Robb Elementary School where 18-year-old Salvador Ramos shot dead 21 people including 19 children?
Officials say Salvador Ramos was inside the school in Uvalde for up to an hour before he was killed.
Steven McCraw, who is the director of the Texas Department of Public Safety, had told a news conference on Wednesday that the gunman was on site for between 40 minutes and an hour before law enforcement were able to "contain" him.
But eyewitness Juan Carranza told the Associated Press that women shouted at officers to "go in there". The 24-year-old, who witnessed the scene at the Robb Elementary School from outside his house, said police did not enter.
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Javier Cazares, whose daughter was killed in the attack, told the news agency he suggested running in with other onlookers because the police "weren't doing anything".
Authorities said the gunman locked himself in a classroom which officers then struggled to gain access to.
It has also emerged that the attacker sent messages on social media about the shooting minutes before it happened.
Texas Governor Greg Abbott said Ramos had promised to shoot his grandmother in private messages sent 30 minutes before the attack.