Camden Council’s legal team has been plunged into crisis after blundering staff accidentally gave the confidential details of alleged victims of anti-social behaviour to the person they complained about.

The council was desperately attempting to retrieve the documents this week, fearing the disclosure could threaten the safety of the five Camden residents affected. All had given evidence about one of their neighbours.

Officials forgot to blank out the details of the witnesses in a bundle of legal papers served to the man, against whom the council is seeking an anti-social behaviour order (Asbo).

The incident has sparked concerns that it will deter people from giving evidence in future for fear of falling victim to a similar data leak.

Cllr Keith Moffitt, leader of Camden’s Liberal Democrat opposition and the group’s crime spokesman, said: “It’s absolutely appalling, this sort of thing absolutely should not happen.

“When people are willing to give evidence confidentially, they need to be confident their identity isn’t going to be revealed and their personal safety should not be jeopardised.”

Cllr Moffitt added that this was a “big mistake” that the council must ensure never happens again.

“Redacting the names is pretty basic stuff, it’s not rocket science,” he added.

The council has yet to report itself to the Information Commissioner’s Office (ICO), a government agency which can issue fines of up to £500,000 for serious breaches of data protection laws.

It has declined to give any further details or respond to questions about how the slip was allowed to happen or the reason for the Asbo application.

The blunder came to light at a public meeting at Camden Town Hall in Judd Street, King’s Cross, last Thursday, which saw residents grill top brass at Camden Police and the Mayor’s Office for Policing and Crime.

The Ham&High has decided not to name the housing estate in the south of the borough that was affected by the data breach, but one resident who lives there spoke at the meeting.

He said: “Can I please ask that this doesn’t happen in the near future and, second, that there is an inquiry or investigation into how it happened?

“This is also involving the Met and it needs a firm commitment. If people do put themselves forward to report crimes – drug dealing, gang fights and so on – at least they should have their details kept safe.”

Cllr Roger Robinson, a Labour councillor for St Pancras and Somers Town, said: “Disclosing this kind of information is wrong and should not be allowed. I’m glad the council is investigating it.”