On Tuesday afternoon, at least 19 students and 2 teachers are dead after a mass shooting at Robb Elementary School in Uvalde, Texas, ABC News reports. One child is in critical condition at a nearby hospital.

The 18-year-old shooter was identified by law enforcement sources as Salvador Ramos, a student at Uvalde High School. He was armed with an AR-15-style rifle and loads of ammunition. According to authorities, he was shot dead by the police.

"He shot and killed horrifically and incomprehensibly 14 students and killed a teacher," Gov. Abbott said during an unrelated press briefing.

According to reports, the shooter also allegedly shot his grandmother, who is critical condition, early Tuesday morning before opening fire on the elementary school.

"When parents drop their kids off at school, they have every expectation to know that they're going to be able to pick their child up when that school day ends. And there are families who are in mourning right now," Abbott said. "The state of Texas is in mourning with them for the reality that these parents are not going to be able to pick up their children."

Two responding police officers were among those injured, Abbott added.

Uvalde Memorial Hospital reported that 15 students were being treated in the hospital's emergency department and two patients were transferred to San Antonio for treatment. Also, University Health in San Antonio said that a 66-year-old woman and a 10-year-old girl were both in critical condition.

According to an Army official, two adult victims of the shooting, are also being treated at Brooke Army Medical Center in San Antonio. Both are in critical condition,

Earlier in the day, the Uvalde Consolidated Independent School District announced that a shooter was located at Robb Elementary School and asked people to stay away from the area.

"There is an active shooter at Robb Elementary," the school district posted on Twitter. "Law enforcement is on site. Your cooperation is needed at this time by not visiting the campus. As soon as more information is gathered it will be shared."

A spokesperson from the Department of Homeland said that Security Secretary Alejandro Mayorkas was briefed on the situation and the agency "is actively coordinating with federal, state, and local partners.”

The National Counterterrorism Operations Center believes there is "no known terrorism nexus" at this time.