A senior member of staff at the Swiss embassy in Tehran has died after falling from the high-rise building where she lived, Iranian media report.
An emergency services spokesman told Mehr news agency that the 51-year-old woman was first secretary at the embassy but did not give her name.
Police in the Kamraniyeh area alerted paramedics on Tuesday morning but she had been "dead for a while", he said.
The Swiss foreign ministry confirmed an employee had died in an accident.
"The Federal Department of Foreign Affairs and its head Federal Councillor Ignazio Cassis are shocked by the tragic death and express their deepest condolences to the family," a spokesperson said.
The ministry added that it was in touch with the family and Iranian authorities.
It gave no further information about the circumstances of the death, citing data protection and privacy reasons.
The Iranian foreign ministry also expressed its condolences, according to the state news agency Irna.
The ministry added that the death was under investigation by the relevant authorities and that the results would be made public soon.
Irna's report cited the emergency services as saying that suicide had already been ruled out.
Switzerland has represented US diplomatic interests in Iran since Washington and Tehran severed relations shortly after the 1979 Islamic Revolution.