Confidential information on a council taxpayer was posted to a third party by mistake.

The application for housing benefit and council tax benefit extended payments gave the man's name, phone number, social security number, date of birth and employment details.

Worthing Borough Council has apologised for the mistake and has promised procedures will be tightened up.

Photographer Eddie Mitchell, from Worthing, discovered the error.

He is in dispute over his council tax and had asked them to send him copies of all information held by the council about him.

He said: "I was looking through the papers when I came across this application form relating to a complete stranger.

"I was shocked. How could this confidential data be sent to someone else?

"How secure is the information held on all council taxpayers?"

Councillor Brian Lynn, chairman of the Tory opposition on the council, said: "This should not happen and I am concerned.

"I will be asking officers to make sure procedures are put in place to ensure this does not happen again."

Colin Smith, borough treasurer, said it was an "extremely regrettable" case of human error when a member of staff was dealing with two bundles of papers.

He said: "We are grateful to The Argus and Mr Mitchell for bringing this to our attention.

"We are tightening up procedures and double-checking anything that leaves our offices."

Mr Mitchell is returning the confidential application form to the council.