Coronavirus could put the hunt for Madeleine McCann on hold if changes to the way the police force operates are introduced.
Plans are reportedly being drawn up to account for 30% of Britain's police force being struck down by the virus, in a worst case scenario situation.
It could mean historical crimes, like the disappearance of Madeleine in May, 2007 would be put on hold.
It could also see forces making officers work 12 hour shifts to make up for a possible 38,000 out of 126,000 being unable to work.
Plain clothes officer may also be put back in uniform to deal with 999 calls.
A government source told the MailOnline : "With fewer officers, the police will be told to prioritise crimes where there is a critical need to investigate or if there is a danger of evidence being lost if they don’t act straight away.
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"The first cases to be parked will be historic investigations, for example the investigation into the disappearance of Madeline McCann.
"In terms of replacing officers, if any armed police officers become sick the plan is to replace them with officers from the civil nuclear constabulary and if they get sick, they will be replaced by the military."
Police are expected to be backed up by 20,000 military personnel drafted in to help with food transportation and the delivery of medical supplies to the most vulnerable.
The military are also likely to be responsible for moving bodies to mortuaries.
Morturies could also be extended - with one at London's Westminter Coroner's Court increased to extra storage capacity of 112 bodies.
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A spokesperson added: "This is a precautionary step and similar arrangements are made during any London-wide response to incidents.
"We hope and trust that this will not be needed but it is sensible to prepare at this stage."
Mirroring NHS plans to re-recruit staff who have left healthcare in a bid to boost staff numbers during the crisis, Metropolitan Police Commissioner Cressida Dick said earlier this week that retired police officers and volunteers could be drafted in.
She said: "We need to be flexible, we are a people organisation and of course it's likely as other people are coming into contact with the virus some of my people will as well.
"We have had plans in place for a long time to be able to move people around, to change people from one role to another, to make sure we protect the really mission-critical services.
"We have not ruled out any option in terms of boosting our numbers.
"We have lots of people who volunteer with the Met, we can bring them in more, and indeed there may be some areas where it would make sense to bring in some retired officers to help us out."
On possible changes to the police force, a National Police Chiefs’ Council spokesman said: "COVID-19 is an unprecedented public health issue and we are all having to move at an incredibly fast pace.
"We will keep our normal business going for as long as we can, however we are prepared to scale back our services to the most critical if we have significant staff shortages. We will give the public information so they know what to expect or do differently in that scenario.
"Maintaining the best service to the public, protecting our officers and staff and supporting the nationwide response are our top priorities."