HACKERS brought down a website for a health trust serving 700,000 NHS patients in Dorset.
The attack, which disabled the site over the weekend, blocked access to the Dorset HealthCare University NHS Foundation Trust website.
The trust provides treatment for mental health issues, addiction, dentistry, and some primary care services to patients across the county.
Hackers posted a message on the site which read: "Don't mess with me. Site totally hacked" and a cartoon image of a penguin emerging from a shattered computer screen carrying a gun.
A jumbled message posted by the hacker on the trust's website read: "You call this security. You must be kidding. If you don't want to get into trouble, patch your admin."
Dr Paul Ton de Vrieze, a lecturer in web systems and technologies at Bournemouth University, said such attacks were often made only for the hacker's satisfaction.
"Sometimes people hack sites for their own bravura. They think it is fun to do and show the world that they are able to do it," he said.
He added that while the attack was illegal, tracing and prosecuting the hacker could be a complicated process, especially if the attack came from abroad.
Dr de Vrieze said that the trust could hire IT specialists to test the site's security with authorised and legal "benign" attacks.
Julie Dean, a spokesperson for the trust, confirmed that the site had been disrupted over the weekend but said it was backed up and had been restored by 9.30am yesterday.
"No personalised, identifiable data or information is stored on the website, so no data has been lost or compromised in any way as a result of this," she said.
"The trust is in discussion with our website provider over measures to limit the site from future, similar attempts to disrupt its viability."