The scare forced Cadbury to withdraw a million chocolate bars

The company announced in December that the bill for dealing with the contamination would reach £30m.

A leaking pipe was blamed for the incident in June 2006.

Birmingham City Council revealed it is to prosecute the company for a breach of health and safety legislation at the plant in Marlbrook, Herefordshire.

Most likely cause

The company is to be prosecuted in relation to three alleged offences, each carrying a maximum penalty of an unlimited fine and/or two years imprisonment, Birmingham City Council said.

The confectionery giant is accused of placing "unsafe" chocolate products on the market.

It will be prosecuted over an alleged failure to "immediately inform" the authorities about the contamination.

The company is also accused of failing to "identify hazards from ready to eat chocolate products contaminated with Salmonella" and failing to "identify critical control points and corrective actions".

The firm has been summonsed to appear before Birmingham magistrates on 15 June, the council said.

One month after the recall, the Health Protection Agency branded Cadbury's chocolate the most likely cause of a salmonella outbreak in more than 30 people.

Investigation ongoing

In a statement, a spokesman for Cadbury said: "We have fully co-operated with the authorities throughout their inquiries and we will examine the charges that have been brought.

"As there is now legal action pending, it would be inappropriate for us to comment further."

The first two alleged offences involve breaches of General Food Regulations 2004.

The third offence is an alleged breach of Food Hygiene (England) Regulations 2006.

A second investigation by Herefordshire Council into possible environmental health breaches at the Marlbrook site is still ongoing.