A data breach affecting more than 400 students at the University of Essex is being treated “very seriously”, the institution said.

Law firm Hayes Connor, which is representing some of those affected, said an email from an external partner of the university accidentally included a spreadsheet containing personal information.

The message from facilities management was to request payment for repairs to a broken door at an accommodation block and was sent on March 23.

The spreadsheet contained more than 400 residents’ information, including student IDs, dates of birth and contact details, Hayes Connor said.

Christine Sabino, the legal specialist at Hayes Connor representing those affected, said it was a “particularly worrying” data breach.

“The spreadsheet included on this email contained all kinds of crucial data on hundreds of people, so the seriousness of the issue should not be downplayed,” she said.

“Through our work, we have seen how breaches of this kind can have a big impact on those affected.

“It should also be remembered that many of the individuals involved here are young adults living away from home for the first time.

“Some may be very worried about this or unsure what to do next.

“The individuals we have spoken to are desperate to know how this happened.“They are also keen to understand what is being done to prevent more issues in the future.

“When individuals provide data to organisations of any kind, they trust that the information will be handled in a secure and proper manner.

“Issues like this only serve to undermine that trust, so we are determined to help our clients get the answers they deserve.”

A University of Essex spokesman said: “We are taking this issue very seriously and ensuring our delivery partners understand our high expectations about the management of data.

“We’ve contacted all individuals involved to offer advice and support.”