Éric Borel was born on December 11, 1978. His parents were Marie-Jeanne Parenti and Jacques Borel, both of whom worked in the military. Their relationship did not last long. After they separated, Éric was sent to live with his paternal grandparents in Limoges until he was five years old. When his mother began a new relationship with Yves Bichet, she took Éric to live with them in Solliès-Pont.

Éric's early life was difficult. His mother was strict and very religious, which made her authoritarian in her parenting. She often mistreated Éric, believing he was a "child of sin." As a result, he never developed a strong bond with her or with Yves Bichet. While Yve Bichet's sons claimed their father was kind to Éric, there were reports of frequent arguments and escalating tensions in the household.

When Éric was eight years old, he broke his arm. Instead of going home, he chose to run away and hide, eventually being found shivering in pain. He was a quiet boy who kept mostly to himself. Éric admired the military, often exaggerating stories of his father's service in the Indochina War. He looked up to his stepbrother Franck Bichet, who was in the army, and he had a fascination with weapons. He would often use an air gun to shoot sparrows.

Éric attended lycée professionnel Georges-Cisson in Toulon and studied electromechanics. He was disciplined and did well in school, but his behavior changed significantly during his last year. He started skipping classes and became withdrawn. He expressed feelings of being overwhelmed at home and often complained about doing housework and being called names. He also voiced a desire to join the military.

Éric had one close friend at school, Alan Guillemette, who was outgoing and popular. Reports about Éric sometimes claimed he had extremist beliefs. This included rumors that his room was full of Nazi items, which stemmed from the actions of his stepfather, who had attended meetings of the Front National. There were also false stories about his family relationships and personal life, but these were not based in fact.

As Éric approached a crisis in his life, he made alarming statements about wanting to harm others.

Éric Borel started a series of attacks on September 23, 1995. The first victim was his stepfather, Yves Bichet, whom Borel shot four times in the kitchen. After that, he attacked his 11-year-old half-brother, Jean-Yves Bichet, while the boy was watching television. Once the two were dead, Borel cleaned the house, covered the bodies, and waited for his mother, Marie-Jeanne Parenti, to return from church. When she came home, Borel shot her in the head.

After the familicide, Borel packed a bag with food, money, and weapons, including a rifle and a pistol. He initially drove away but crashed his car into a wall. He then continued on foot. Meanwhile, the bodies of his family were discovered by Jean-Luc, Yves's son, who called the police.

The following morning, at around 7:15 a.m., Borel visited his friend Alan Guillemette. After a discussion, he shot Guillemette in the back. Starting around 7:30 a.m., Borel opened fire on random people in the village of Cuers. He shot through windows and targeted individuals in the street, including Denise Otto, who was taking out the trash, and Ginette Vialette, who was shot while inside a house.

Borel continued his rampage, killing a total of twelve more people throughout the morning. He shot a shopkeeper, people using an ATM, and even an elderly woman walking her dog. By 8:00 a.m., police arrived at the scene. Realizing he was trapped, Borel shot himself under a tree.

In total, Borel killed 16 people, including his family and victims from the shooting spree. The incident caused a significant shock to the local community and was noted as one of the deadliest acts of mass murder in France at that time.