The Yorkshire Ambulance Service NHS Trust has launched an investigation into two of its staff members over possible unauthorised access to the medical records of William Chapman, a man who died in a tiger attack at the Yorkshire Wildlife Park, the trust has announced.

According to the trust, there were two instances in which two staff members accessed or attempted to access data about the incident and medical information without a valid reason. The service stated that the potential breach of data confidentiality was identified following the attack and that the case has been reported to the Information Commissioner's Office.

The trust stated that it "identified an issue with the management of information related to this tragic incident at the Yorkshire Wildlife Park" and that William Chapman's family had been informed of the ongoing investigation. It added that it takes "patient data privacy very seriously" and has "robust information protection systems", with the issue identified through proactive audits.

The ambulance service responded to emergency calls on Saturday, when Chapman climbed into the tiger enclosure at the Yorkshire Wildlife Park. Chapman, 23, was killed by a 200kg male Siberian tiger named Altai. Park staff secured the tiger, while paramedics from the ambulance service confirmed Chapman's death at the scene.

At the opening of the inquest on Thursday, it was stated that Chapman suffered from schizophrenia and had experienced episodes of psychosis, but was "highly functional and independent, with no care needs". He was a self-employed online trader who was living in Doncaster at the time of his death. His family, who did not attend the hearing, expressed concern about his contact with mental health services prior to his death. The Rotherham, Doncaster and South Humber NHS Foundation Trust has launched an investigation into its contact with him.

According to court official Caitlin Brookes, "the tiger approached him, and the physical contact that followed resulted in multiple traumatic injuries that caused death quickly". The preliminary post-mortem examination showed that he died from multiple traumatic injuries. Coroner Nicola Mundy stated that her office is awaiting a detailed report on the severity of Chapman's injuries before the full inquest scheduled for 18 March.

The park reopened on Friday after being closed following the attack. Before opening, the Yorkshire Wildlife Park stated that safety was "the highest priority" and thanked the public for "messages of support and love for our team at this time". Experts in wildlife and zoological parks told the Guardian that it is unlikely the park could have done anything to prevent the death.