Salvador Ramos shot dead 19 students and two teachers in a Texas elementary school. There could probably have been many more victims, but one teacher saved herself and her students thanks to a trick: the active shooter drill.

The day after, the small town of Uvalde is still bewildered. 19 children and two teachers are dead. Shot by an 18-year-old. It’s one of the worst school massacres in America in years.

And probably there could have been many more deaths if one teacher hadn’t reacted with the presence of mind. As the “mirror” reports, when she heard the first shots, she turned off the light and ordered her students to hide.

“The children then crawled under the tables,” reports a mother of a surviving child to the “Spiegel”. Salvador Ramos, therefore, walked past the darkened classroom armed with an AR-15 rifle. A few doors down he set up his bloodbath.

The teacher, who, according to “Spiegel”, stood in for a colleague that day, saved her students’ lives – because she uses a procedure that almost all teachers and students in the USA practice regularly. The so-called “active shooter drill.”

Behavior during rampages, such as locking doors and barricading in classrooms, is practiced. This includes turning off the lights.

The “active shooter drill” is also controversial in America, studies see a connection with anxiety and stress.

In the case of Uvalde, however, it has at least shown that it can work – if only for one class.

Also read: 15 minutes before the crime, a girl from Frankfurt who ran amok revealed his plan