A laptop containing the unencrypted personal details of 109,000 Pensions Trust members has been stolen from the offices of HR software and services provider NorthgateArinso.
NorthgateArinso, which provides the Pension Trust's computerised admin system, was using the laptop as a database for development, training and performance testing at its offices in Marlow in Buckinghamshire.
The password protected machine, stolen on 23 March, contained personal details, accurate as of May 2007, for members of six of the Pension Trust's 39 schemes.
It contained names, addresses, dates of birth, national insurance numbers, names of employers, salary details, information on nominees and, for those in receipt of a pension, bank account details.
The Pension Trust says the police and NorthgateArinso think "this was an opportunistic theft and that the laptop itself was the thief's target".
It has sent out letters to those affected, reported the theft to the Information Commissioner and the pensions regulator and appointed fraud prevention service Cifas to protect affected members.
In addition, NorthgateArinso has had its access to personal member data withdrawn and instructed to delete any existing information it holds.