The woman, who lived in Norrkoping, died at home in March, The Local.se reported. A doctor pronounced her dead, but no arrangements were made to remove her body.
In April, when relatives began asking about the funeral, officials realized nothing had been done.
"The body was completely rotten, the relatives couldn't go into the apartment because the stench was so strong," the wife of a nephew told a newspaper, the Norrkopings Tidning.
Jaan Timoleon, head of Neron, the company that employs the doctor, said there was a "misunderstanding."
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