The Co-operative Group has apologised after data relating to 83,000 of its customers was accidentally made available online.

The group says a third party service provider was responsible for the data breach, which affected customers of its Life Planning and Wills & Funeral Planning divisions. The data in question was "non-sensitive" as defined by the Data Protection Act, it said.

"As a result of an error at a company which provides technical support services to Co-operative Life Planning (CLP), the security of some data was lowered," the group said in a statement. "We take our responsibilities to our customers extremely seriously and we have written to all the approximately 83,000 customers affected."

The timing of the breach is unfortunate for Co-operative Group, which announced this week that it will offer legal advice from its high street bank branches later this year.

Last year, the Co-operative Group launched a risk management system that was built in collaboration with Hitachi Consulting. According to a press release issued by Hitachi, the implementation included functionality designed to reduce the risk of data protection breaches.