Birmingham-based pub chain Mitchells & Butlers (M&B) has been fined £1.5 million after a diner at one of its pubs died following a Christmas dinner there.

In addition, a pub chef and his manager have both been jailed after the Christmas dinner they served at the Railway, in Hornchurch, left dozens of other customers ill with food poisoning.

Mehmet Kaya and Ann-Marie McSweeney, the chef and manager of the east London pub, were jailed at Snaresbrook Crown Court for 12 months and 18 months respectively for perverting the course of justice and both ordered to pay £100 in costs.

The pair hindered investigations into the deadly food poisoning by lying to police and forging records relating to the cooking of the turkey meat.

M&B, whose head office is in Fleet Street, was ordered to pay £227,500 costs in addition to fine after being found guilty of placing unsafe food on the market.

Della Callagher, a 46-year-old mother of one, died two days after eating the four-course Christmas meal at the pub in December 2012 which left a further 33 people ill.

Havering Council carried out a year-long investigation into the incident which found the reason for the illnesses was food poisoning, caused by Clostridium perfringens bacteria, because the turkey meat was either not cooked adequately or not reheated properly.

In a statement, M&B said: "We deeply regret this matter and have taken it extremely seriously.

"As soon as we learnt of the incident, M&B conducted a full and thorough independent investigation and referred our findings to the London Borough of Havering immediately.

"This case also relates to the conduct of two former employees (who) had committed acts which were not in accordance with Mitchells & Butlers' food safety procedures and practices.

"The conduct....was entirely their own actions and in no way represents conduct acceptable to, or condoned by, M&B.

"The prosecution accepted that these procedures, if they had been properly followed by those involved at the time, would have prevented this terrible event but we have nevertheless conducted a detailed assessment of our policies, procedures and training since the incident to identify any possible improvements."