A cleaner who worked hard to provide for her kids has been accidentally shot in the head by a man trying to kill his former school bully.

Mariela Marquez, 34, was shot in the head in the office where she worked as a cleaner in the town of Yerba Buena in the Argentine province of Tucuman.

The alleged perpetrator was 29-year-old Geronimo Helguera, who reportedly entered the workplace in a rage looking to kill a former classmate who allegedly bullied him in high school.

Witnesses later told the police the man was carrying a gun and seemed out of his mind at the time of the shooting.

After being accidentally hit in the head by a bullet, the victim was taken to Hospital Padilla in a critical condition. Despite the doctors’ best efforts, she succumbed to her injuries the following day.

The target of the suspect’s attack was reportedly a man whose surname was stated as Ledesma.

After insulting and threatening Ledesma, the suspect opened fire, but the bullet hit the cleaner, who was passing through that part of the office at the time.

The suspect was arrested and taken to the local police station, and cops were also able to retrieve the alleged murder weapon he had thrown into a street bin.

Judge Isabel de los Angeles Mendez referred him for a psychiatric examination and, upon conclusion, his admission to the Obarrio Psychiatric Hospital in the state capital of San Miguel de Tucuman was ordered.

The victim’s brother-in-law, Gustavo Campos, revealed the victim was a mother, telling reporters she cleaned offices, buildings and galleries “so her children were never left lacking anything”.

Former classmates of the suspect confirmed he had gone to high school with Ledesma, but they said they did not recall any problems between the two.

The suspect’s assigned lawyers, Ernesto Basclini and Camilo Atim Antuni, highlighted that the suspect had “been on medication for a long time” and described the incident as “a real tragedy”.