The US police published a video on YouTube, documenting the moment police killed the shooter who killed 6 people at an elementary school in Nashville, the capital of the US state of Tennessee.

The video, recorded on a camera mounted on the body of a policeman, shows the moment police officers entered the school building and clashes with the shooter took place in one of the school halls.

Police said the shooter, who killed three children and three staff at a Christian school in Nashville on Monday, was a former student and carefully planned the attack with detailed maps and surveillance.

Nashville Police Chief John Drake identified the suspect as Audrey Hill, 28, who later said she was transgender.

Drake said Hill, who was killed by police, left behind a statement and maps of the school detailing observation points, entry and exit, and was "prepared for a confrontation with law enforcement."

Hill with a pistol and two assault rifles stormed a side entrance to The Covent, a Christian academy, and made her way while shooting, according to police.

Police identified the victims as a six-year-old and two nine-year-olds, while the three adults killed were between the ages of 60 and 61.

One of the victims was the school's principal, Catherine Kuns, according to the academy's website.

Following yesterday's attack, the White House again called on Congress to work on legislation that would place restrictions on assault weapons, while US President Joe Biden called the shooting at The Covent School "abhorrent" and stressed that armed attacks were "tearing the soul apart" of the United States.

According to news reports, the attack on the school was the 129th mass shooting in the United States this year.