Cape Town - All three members of the Van Breda family who were murdered in their home on the De Zalze estate in Stellenbosch last year succumbed to serious cuts to their skulls.Netwerk24 reported on Wednesday that this information is contained in forensic reports which will be used in the trial of Henri van Breda, 21, who is charged with murdering his parents, Martin and Teresa, and older brother Rudi. His younger sister, Marli, was seriously injured in the attack. Henri faces three counts of premeditated murder, one of attempted murder and one of obstructing the course of justice. He handed himself over to police earlier this month and was granted bail of R100 000 on June 14. His trial will start in the Western Cape High Court on September 9. - Read more: 8 things you should know about the State's case against Henri van BredaThe forensic reports, which were gained by Eikestadnuus, detail how Martin, Teresa and Rudi had severe cuts to the right side of their skulls and that this was the cause of their deaths. Several other wounds were also found on their bodies. An axe, weighing 4.5kg, was used in the attack and recovered from the scene. The impact blows were about 500kg/cm². A kitchen knife was also recovered from the scene. Henri was found at the house after the murders wearing sleeping shorts and white socks. DNA analysis of the blood found on him and his clothing matches the DNA of his dead family members.Henri was also wounded, but these wounds were superficial and the State said it has expert medical opinion that the wounds were self-inflicted. He is also accused of tampering with the crime scene and supplying false information to the police.The investigation into the murders lasted for more than 16 months, but the National Prosecuting Authority now believes it has enough evidence to begin the trial.Meanwhile, Marli van Breda's advocate, Louise Buikman, did not respond to Netwerk24 questions on Marli's condition. Earlier this month, Buikman told News24 that Marli is aware that Henri had been arrested and "the news is understandably very distressing to Marli". She confirmed that Marli was in contact with her brother.