An alleged spy from the United Arab Emirates under investigation for the killing of dissident Saudi journalist Jamal Khashoggi was found dead in his Turkish prison cell, according to a report on Monday.

Prison wardens found the man, identified as Zaki Y.M. Hassan, hanged inside his solitary cell in Istanbul’s Silivri prison and launched an investigation into his death, the Wall Street Journal reported, citing Turkish prosecutors.

Turkish state media said Hassan died by suicide.

Authorities in Turkey were investigating Hassan and another man in connection with Khashoggi’s killing last October at the Saudi consulate in Istanbul by Saudi Arabian operatives.

The two men arrived in Turkey after Khashoggi’s Oct. 2 killing and were detained on April 15.

They confessed to spying for the United Arab Emirates.

Turkish state media said the two were collecting information about Arab nationals living in Turkey and were trying to recruit people for a surveillance network.

Prosecutors in Turkey offered no details about Hassan, his age, or his nationality.

They didn’t identify the second suspected spy.