Police say they are looking at possible manslaughter charges over the deaths of two workers at Banham Poultry more than three years ago.

Two pest control subcontractors Jonathan Collins, 34, from Watton, and Neil Moon, 49, from Spalding were found dead in the early hours of October 4, 2018, at the Attleborough chicken factory.

Norfolk police and the Health and Safety Executive (HSE) launched an investigation but until now have said little about it.

However, Detective Chief Inspector Phil Gray, who is leading the case, said: “This is a very complex investigation that is going to take time.

“Any investigation which relates to companies as well as individuals complicates matters and you have to work very closely with companies in charge of Banham Poultry and that elongates the process in terms of what failings have happened, if any at all.”

He said police were investigating possible charges of gross negligence, manslaughter and corporate manslaughter.

HSE, meanwhile, is also looking at non-criminal, health and safety offences, he said.

The ownership of the business has changed twice since the tragedy.

The day after the deaths, Banham Poultry’s owners announced the factory had been bought by a company called Chesterfield Poultry after several days of negotiations.

Then last month the business was sold to the private office of 2 Sisters Food Group founder Ranjit Boparan.

However, DCI Gray said the company changing hands did not affect the investigation.

He also said police were in regular contact with the men’s families to keep them updated.

Both of the families paid emotional tributes to the two fathers at the time of their deaths.

Mr Collins’ fiancée, Sara Dutton, previously said: “It’s a terrible accident that never should have happened. He went to work one day and never came home.”

Emergency services were called to the site around 1am on October 4, 2018.

According to reports at the time, there was a suspected gas leak, but the cause of the deaths, normally confirmed at an inquest, has not been publicly announced as the inquest has been adjourned several times while the police investigation is ongoing.

We have contacted Banham Poultry.