“This is a terrible failure for the tax agency. People with protected identities are generally crime victims, abused and persecuted women, witnesses under threat, judges, police officers and journalists. Their lives could depend on not being detected,” said a source close to the investigation to daily Expressen.

According to the paper, county police and tax agency IT specialists are busy investigating just how many personal details might have leaked out during the suspected attack, which was detected last week.

The breach occurred at the IT-company Logica, which supplies several government agencies with information from the tax authority’s public register.

“This is a serious incident. We have never experienced something like this before,” said Anders Sandell, head of security at the company, to Expressen.

The tax agency has confirmed to Expressen that a number of personal identity numbers have been accessed in the breach, of which about a thousand were of people with protected identities.

However, the experts are still unsure whether any other information, such as address or other contact details, had been accessed at the same time.

“We are just saying that there is a theoretical possibility that other details have been copied,” said Anders Kylesten, head of security at the tax agency, to Expressen.

However, Kylesten still sees the breach as a “serious” one.

“We are doing everything we can to handle any potential consequences of this, but it is important not to frighten people who are already living in fear, if there is no reason,” he told the paper.

The Local/rm