A mortuary worker has been suspended at a hospital where a Muslim woman's body was desecrated in January.
Police say they have found another case of desecration
Hillingdon Hospital in west London confirmed the man worked in the hospital mortuary, where 65-year-old Habiba Mohammed's body was found with rashers of bacon placed on her.
It is strictly against the Muslim religion to eat or touch pork.
Detectives have also learned another corpse was defiled in the mortuary - a white woman found with pen marks on her body in 1996.
And 2,000 photographs of bodies, believed to have been taken over 10 years, have been seized by officers.
They were found in a raid on the house of a 53-year-old man arrested on 1 May over allegations of theft in the mortuary - he has since been released on police bail.
Scotland Yard said the bodies in the photographs showed no evidence of desecration.
This cannot be allowed to happen again, in our hospital or any other
David McVittie, chief executive of the Hillingdon Hospital NHS Trust
"At this stage there is no evidence to link the four crimes - the two desecrations, the allegations of theft and whether the photos were illegally taken," the spokeswoman said.
"However, due to the fact that the alleged offences could have taken place at the same location they are being investigated together."
Police have contacted the family of the 1996 victim, who have released a statement saying how shocked they were by the news.
It read: "The death of our loved one was very sudden and unexpected.
"We had just come to terms with it when we were told of this grotesque incident.
"We hope that whoever is responsible is brought to justice."
Anyone concerned about relatives or friends who died at Hillingdon Hospital can ring the hospital on its special hotline: 01895 238 282
David McVittie, chief executive of the Hillingdon Hospital NHS Trust, said it had launched its own inquiry and no-one is now allowed to work in the mortuary alone.
"If anyone who worked for us interfered with bodies in the mortuary that is a deeply shocking fact.
"This cannot be allowed to happen again, in our hospital or any other," he said.
Police asked anyone who had any information about the desecrations to contact them and said a £5,000 reward was being offered for information.
A 20-year-old man and a 30-year-old man, believed to be former mortuary workers, were arrested separately last month on suspicion of causing a nuisance in a public place.
Both men were released on police bail until later this month, pending further inquires.
The Metropolitan Police have asked anyone with information about the inquiry to contact the incident room on 020 8247 5229.