Four Chelsea Pensioners have died from "COVID-19 related" illnesses, the Royal Hospital Chelsea has said.
It said a further 15 residents have recovered after either testing positive for the virus or developing symptoms.
Royal Hospital Chelsea is home to around 290 military veterans.
A Royal Hospital Chelsea spokesperson told Forces News: "We continue to review the measures in place in the Royal Hospital in light of our own detailed analysis, of the clinical and scientific data available from outside and mindful of current and emerging Government, NHS and Public Health England advice.
"Our staff continue to work tirelessly to care for and provide all the support needed for the pensioners, many of them having volunteered to move into the Royal Hospital to reduce the risk of further ingress of the virus from outside."
It comes as the Government has vowed to test all care home residents and staff with COVID-19 symptoms for coronavirus.
Currently, only the first five symptomatic residents in a care home setting are tested to provide confirmation of whether there is an outbreak.
On Monday, England's chief medical officer, Professor Chris Witty, said 92 care homes in the UK had reported coronavirus outbreaks in the space of just 24 hours.
Sir David Behan, non-executive director of HC-One, the UK's largest care home operator, said on Tuesday that COVID-19 is present in around two-thirds of its care homes.
General Sir Adrian Bradshaw, Governor at the Royal Hospital Chelsea, said a small team from the British Army have been drafted in to provide "a range of specialist medical support" to the hospital.
"Since our foundation, the hospital has endeavoured to honour the debt the nation owes to its veterans by providing our pensioners with the highest quality care and support that they rightly deserve," he said.
The Royal Hospital Chelsea has been looking after British Army veterans since the end of the 17th century.