The managing director of a council, who advises local authorities on cyber security, says no organisation is 100% safe from cyber attacks.

Gloucester City Council's computer systems were crippled by hackers four years ago which cost about a million pounds to put right.

Despite better protections and firewalls, there is a concern that the number of councils across the country make them a target because they are a government body, and there are many of them.

Jon McGinty, managing director of Gloucester City Council, said organisations have a "duty" to minimise and mitigate risk.

He said: "I think we also have a duty to prepare for the possibility that the hackers do get through some chink in someone's armour and can attack us."

When the Gloucester City Council was hit by hackers in December 2021, the group demanded ransom payment for decrypting all of the council's servers and threatened to release sensitive data onto the "dark web".

Mr McGinty said: "Everything became slower or harder to achieve."

"One of the impacts that really affected Gloucester residents was land searches for people moving house, and our land searches system was beyond control – it wouldn't work.

"So people were struggling to get a mortgage because they couldn't do a land search on a property they were looking to buy, so the whole of Gloucester's house market froze up for a number of months."

Mr McGinty told the BBC the gang targeting Gloucester City Council fell out with each other after the Russian invasion of Ukraine, so no further demands were made.

Despite now being better protected than ever before, the city council still get thousands of attempted attacks on its IT system every week.

The former head of the National Cyber Safety Centre (NCSC), Ciaran Martin, said his "biggest cyber-security worry" is the threat of simultaneous attacks on public services, like councils and hospitals, which has the potential to "wreck lives".

According to the Information Commissioner's Office, there were 41 ransomware attacks on local councils in 2024.

The government said it was "taking action to protect local councils by providing funding to increase their cyber defences".

Mr Martin fears the attack on the council, and other public services, could have "shown hostile nation states how to disrupt our society".