Iran executed two men in separate cases on Wednesday, accusing one of spying for Israel and another of being a member of the Islamic State group, state media reported.

A report by the judiciary news website Mizanonline identified the alleged spy as Rouzbeh Vadi, who was accused of relaying classified information to Israel’s intelligence service, the Mossad.

Authorities said Vadi provided information about an Iranian nuclear scientist who was killed during Israel’s June air strikes on Iran, according to the report, which did not identify the scientist or the time and place of Vadi's arrest.

Vadi met the Mossad officers five times in Vienna, Austria, the report said.

Israel launched 12 days of air strikes in June, targeting Iran's top generals and nuclear scientists. Iran retaliated with barrages of missiles and drones.

The Israeli offensive killed senior military commanders, nuclear scientists and hundreds of others, striking both military sites and residential areas.

According to local media, at least a dozen nuclear scientists were killed.

Iran has, since the war, vowed swift trials for people arrested on suspicion of collaborating with Israel.

Iran separately hanged a member of Daesh on Wednesday after he was convicted of plotting sabotage, Mizanonline reported.

Officials accused Mehdi Aghazadeh of being a member of Daesh who participated in military training in Syria and Iraq before illegally entering Iran with a four-member team who were killed in a fight with Iranian security, the news site reported.

Authorities said Iran’s Supreme Court upheld the sentences of lower courts and followed full legal procedures before executing both men, Mizanonline reported.