The company also plans to expand the production of Lea and Perrins sauces by a third to 12, 500 tonnes by the end of 2013.

FORBES: H.J. Heinz's Earnings To Show Growth But Slimmer Margins

Mr Perrins said when police arrested them in Scotland, they found ammunition, instructions and a cleaning brush for the gun in the boot of the Escort, and a checklist Mr Cowan had prepared.

BBC: Andrew Farndon

Mr Perrins said mobile phone data placed Mr Cowan outside West Suffolk Hospital on the day of the hold-up, and his DNA was found on a balaclava and on the inside of a case which the prosecution say contained the gun.

BBC: Andrew Farndon