Bombers are believed to have targeted charity workers in the latest of a spate of letter bomb attacks in north England and Wales.

North Yorkshire Police revealed that two lethal packets were mailed to a charity organisation in Lytham St Annes, Lancashire, and an agricultural supply shop in Sheffield.

They are being linked with the recent letter bomb attacks in Masham, Wensleydale, and Patrington, East Yorkshire, and five other places in Cheshire, North Wales, the West Midlands and Northumberland.

North Yorkshire's deputy chief constable Peter Walker, who is overseeing the hunt for the bombers, said: "Yet again we have indiscriminate attacks on law abiding people going about their daily business. How volunteers working for charity can be viewed as a legitimate target in a bombing campaign is beyond me.

"We are determined to trace those responsible and all forces concerned are working closely together in a concerted effort to bring this about."

Nobody has claimed responsibility for the letter bombs.

Updated: 08:28 Wednesday, January 31, 2001