Editor’s Note: On June 21, the director of the Texas Department of Public Safety, Steven McCraw, gave a new timeline of what happened during the Uvalde massacre when he testified before a state Senate panel. The following timeline is based on information McCraw gave at a news conference on May 27, three days after the shooting.

CNN  — 

As a broken community tries to make sense of a massacre that took the lives of 19 young children and two teachers, authorities have offered shifting timelines of what happened inside the Uvalde, Texas, school.

On Friday, May 27, Texas Department of Public Safety Director Steven McCraw laid out the most detailed breakdown the public yet had gotten about the horror that unfolded in Robb Elementary School on May 24 – and tried to offer some answers about how authorities responded. Four days later, they clarified more, including that the shooter entered the school through a door that was closed but not locked.

Among the details we know now are: a school officer drove right past the shooter, 18-year-old Salvador Ramos, as he hunkered by a vehicle; as many as 19 officers were inside the school more than 45 minutes before the suspect was killed; the school district police chief decided not to breach the classroom where the shooter was; and a young girl from the class called 911 several times asking for police while authorities were right outside.

CNN created this timeline of events with information provided by McCraw, social media posts and other reporting that offers a look into what came before the shooting and a minute-by-minute breakdown into the attack – and how authorities responded to it.

Steven McCraw, director of the Texas Department of Public Safety, speaks during a press conference on May 27, 2022.

In the months prior

In September 2021, the shooter asked his sister to help him buy a gun and she “flatly refused,” McCraw said.

The shooter was in a group chat on Instagram and in it, there was a February 28 discussion of the suspect being a “school shooter,” McCraw said.

On March 1, the shooter had an Instagram chat with several others in which he discussed buying a gun, McCraw said. Two days later, there was another group chat in which someone said, “word on the street” was that the suspect was buying a gun. The shooter replied, “just bought something rn.”

On March 14, the shooter wrote in an Instagram post, “10 more days.” Another user replied, “‘are you going to shoot up a school or something?’ The shooter replied, ‘no and stop asking dumb questions and you’ll see,’” McCraw said.

On May 17 and May 20, the shooter legally purchased two AR platform rifles at a local federal firearms licensee, said Texas state Sen. John Whitmire, who received a briefing from law enforcement.

The shooter also purchased 375 rounds of ammunition on May 18, Whitmire said, citing law enforcement.

State Sen. Roland Gutierrez said the purchases were made for the suspect’s 18th birthday.

He shot his grandmother and left the house

Before going to the school and committing a massacre, the shooter sent a series of chilling text messages to a girl he met online, according to screenshots reviewed by CNN and an interview with the girl.

The teen girl, who lives in Germany, said she began chatting with the shooter on a social media app earlier this month. The shooter told her that on Monday, he received a package of ammunition, she said.

On Tuesday morning, Ramos called her and told her he loved her, she said.

He complained about his grandmother being on the phone with AT&T about “my phone.”

“It’s annoying,” he texted.

Six minutes later, at 11:21 a.m., he texted: “I just shot my grandma in her head.”

Seconds later, he said, “Ima go shoot up a(n) elementary school