Texas killer sent Facebook message warning 'I'm going to shoot an elementary school' 15 minutes before rampage
Tears outside the Willie de Leon Civic Center in Uvalde, Texas after a gunman killed 19 small kids and two teachers at an elementary school. (AFP)

A Texas gunman sent three chilling messages on Facebook in the half hour before killing at least 19 children and two adults at Robb Elementary School, according to Texas Gov. Greg Abbott.

Salvador Ramos sent the messages using his personal Facebook page, which was taken down shortly after the massacre in Uvalde left nearly two dozen people dead, including the 18-year-old gunman, the governor said Wednesday.

"I'm going to shoot my grandmother," Ramos said about 30 minutes before going to school, and he followed up by saying that he had carried out that threat. "I shot my grandmother."

About 15 minutes before going to Robb Elementary, Ramos warned that he was on his way -- but didn't specify where.

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"I'm going to shoot an elementary school," Ramos warned.

A spokesperson for Facebook said that the messages described by Abbott were “private one-to-one text messages that were discovered after the terrible tragedy occurred.”

The attack in Uvalde -- a small community about an hour from the Mexican border -- is the latest in a spree of deadly shootings in the United States, where widespread horror at gun violence has failed to spur action to head off future killings.

The assailant "shot and killed, horrifically and incomprehensibly, 14 students and killed a teacher," Abbott said Tuesday. The governor said the suspect, a local teenager, was also "deceased," adding that "it is believed that responding officers killed him."

Abbott said the shooter was believed to have "abandoned his vehicle and entered into the Robb Elementary School in Uvalde with a handgun, and he may also have had a rifle."

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The school -- which teaches more than 500, mostly Hispanic and economically disadvantaged students from second through fourth grade -- called on parents not to pick up their children until all were accounted for.

"Please do not pick up students at this time. Students need to be accounted for before they are released to your care. You will be notified to pick up students once all are accounted for," the school said on its website.

Ted Cruz, a US senator from Texas, tweeted that he and his wife are "lifting up in prayer the children and families in the horrific shooting in Uvalde."

(Note: This article has been updated after Facebook released a statement about the incident.)

With additional reporting via AFP

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