NHS staff may have improperly accessed information about the man killed by a tiger at Yorkshire Wildlife Park.
William Chapman, 24, died after entering the enclosure at the attraction in Doncaster on Saturday.
Yorkshire Ambulance Service Trust said it believed two staff had accessed or tried to access "incident/medical information... without a legitimate reason to do so".
It said the concern had been identified following "proactive audits".
The trust has started an investigation "to establish the full circumstances surrounding these potential breaches and the actions of these individuals".
It said the Information Commissioner's Office (ICO) had been informed and William's family would be kept up to date.
An inquest opened on Thursday and heard Mr Chapman died from "multiple traumatic injuries" following contact with the tiger.
It heard he was previously diagnosed with schizophrenia and had suffered bouts of psychosis. His family have expressed concerns about his contact with mental health services before his death.
A full inquest is set to be held in March next year.
There have been other instances of NHS staff accessing medical information on high-profile cases without a legitimate reason.
The child attacked by a crocodile at a zoo in June had their records accessed by dozens of staff.
Southport attack survivor Leanne Lucas also had her records inappropriately accessed and was not told until two years later.
Eleven staff were also sacked for accessing the records of the 2023 Nottingham attack victims.
The head of the NHS warned staff last month they faced immediate suspension if caught.
A Sky News investigation found nearly 3,000 data breach cases had been investigated by the NHS since 2021, many involving ordinary patients. Just over 400 were referred to the ICO.
Some 67% of cases resulted in minor punishment; such as an informal, verbal, or written warning, or no further action.
But of the 134 who responded to our Freedom of Information requests, only 54 said they routinely looked for potential breaches.
(c) Sky News 2026: Man killed by tiger may have had medical records breached by NHS staff

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