Two men were found dead on Sunday at a nursing home in south-east London.
A man aged 40 and a woman aged 33 have been taken to hospital in stable condition.
It is not clear whether they died at the nursing home or elsewhere.
The coroner said the deaths happened at the Sunnysides Nursing Home, which is owned by the National Health Service.
The man, a father of two, died from a heart attack at about 2pm and the woman from a cardiac arrest, the coroner’s office said in a statement.
The home was not open on Sunday but staff had been told to take extra care and were checking CCTV to ensure the deaths were not suspicious.
The deaths happened just days after the death of a woman at the Nursing Home of Southport, which was closed to the public after an attack on staff last month.
At least six people were injured in the attack and a man was charged with murder.