Minnesota school shooter Robin Westman made a final plea to her family and friends in a suicide note she penned before she slaughtered two children at mass.

Westman, 23, posted the note to a now-deleted YouTube page just hours before she shot through stained glass windows at children sitting on the pews inside Annunciation Catholic School's church on Wednesday morning.

Two children aged eight and 10 were killed in the attack and at least 17 other victims - 14 children and three adults - were injured before Westman turned the gun on herself, according to authorities.

She explained in her note why she decided to carry out the attack in Minneapolis, as she apologized to her family and friends - and offered one final request.

'Pray for the victims and their families,' Westman concluded her rambling note, despite having a rifle magazine labeled 'For the children, hahahahahahaha.'