ISTANBUL, Nov 25, 2025 (BSS/AFP) - A family-of-four who died while visiting Istanbul on holiday from Germany in mid-November were poisoned by a gas that is used to treat pest infestations, Turkish media reported on Tuesday.

Citing the autopsy report handed to the prosecutor's office on Tuesday, the independent Halk TV broadcaster and news website T24 said that while no dangerous substances were found in the food they ate, the investigation had "detected a strong presence of phosphine gas".

The findings appear to confirm the theory that the Bocek family died after being exposed to the toxic insecticide as a result of a pest control treatment used by the hotel they were staying in.

"Proof has been found that this chemical product was used by the hotel," the report added, indicating that there was "solid proof" that the family "died as a result of phosphine gas".

After falling ill on November 12, the family's four members died within days of each other, with the two children, aged three and six, the first to succumb, followed successively by the mother then the father.

Investigators had originally had suspicions about food poisoning, as the family had visited the tourist neighbourhood of Ortakoy for street food prior to the deaths.

But that suspicion was quickly dismissed, as Turkish media reported the hotel they were staying in was dealing with a bedbug infestation, with the insecticide gas believed to have seeped into their room through a ventilation duct in the bathroom.

The hotel has since been shut and 11 people have been arrested.