Jacob Albarado and police at the scene helped evacuate students from the school (Picture: Facebook)

An off-duty Border Patrol officer rushed to Robb Elementary School to help rescue 20 children after being alerted to the Texas shooter.

Jacob Albarado was about to sit down for a haircut when he received a text from his wife Trisha, a fourth-grade maths and science teacher at the school, saying: ‘There’s an active shooter. Help.’

Grabbing his barber’s shotgun, he hurried to the school where his wife and one of their children, eight-year-old Jayda, were inside.

The teacher and her students were hiding under desks behind curtains while Jayda was locked in a bathroom.

The tactical team were already poised to enter the wing where the 18-year-old gunman was barricaded when Albarado and his barber arrived but – desperate to find his wife and daughter – he made a plan with law enforcement at the scene to evacuate as many children as possible.

As two officers provided cover – guns drawn – two others guided children from the cleared rooms onto the sidewalk.

‘I’m looking for my daughter, but I also know what wing she’s in. So I start clearing all the classrooms in her wing,’ he told New York Times.

Trisha Albarado sent a desperate text to her husband while hiding with her students (Picture: Facebook)

Mr Albarado helped rescue 20 children including his daughter (Picture: Facebook)

It was then Mr Albarado spotted his daughter, giving her a hug before continuing to keep the other children moving along.

‘They were just all hysterical, of course,’ he said.

Meanwhile, the gunman continued sporadically at the walls and door until the tactical team entered the room and shot him dead.

Mr Albarado confirmed one of his daughter’s friends was among the students killed, and called for more armed guards at schools to prevent another shooting.

‘As I’m putting my daughter to sleep, she tells me her team mate’s sister passed away today, and it was her friend also,’ he wrote on Facebook in the early hours of Wednesday.

‘I’m so angry, saddened and grateful all at once. Only time will heal their pain and hopefully changes will be made at all schools in the US, and teachers will be trained and allowed to carry in order to protect themselves and students.’

Two adults and 19 children were killed in the masscare (Picture: Reuters)

The gunman killed 19 children – the youngest of whom was eight years old – and two teachers at the school in Uvalde, marking the deadliest school shooting since 2012’s Sandy Hook Elementary massacre.

He had first shot his grandmother in the face before stealing a truck, crashing it by the school, and beginning his rampage.

The teenager remained holed up in a classroom on the premises in a stand-off with police officers for up to an hour before they forcibly entered the room, and he was shot dead by a Border Patrol agent.

More: US news

President Joe Biden – who is expected to visit the school in the coming days – appeared to call for tougher gun restrictions in the wake of the massacre.

‘As a nation we have to ask when in God’s name are we going to stand up to the gun lobby? When in God’s name are we going to do what has to be done? Why are we willing to live with this carnage?’ he asked.

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