Iran on Saturday executed a once-exiled journalist over his online work that helped inspire nationwide economic protests in 2017, authorities said, just months after he returned to Tehran under mysterious circumstances.

Iranian state television and the state-run IRNA news agency said that Ruhollah Zam, 47, was hanged early on Saturday morning. In June, a court sentenced Zam to death, saying he had been convicted of "corruption on Earth," a charge often used in cases involving espionage or attempts to overthrow Iran’s government.