The executed man, Rouzbeh Vadi, had previously worked in one of the Islamic Republic's most "important and sensitive organizations" - where he gained secretive information to hand to Israel, the Iranian government claims.

State media says he "committed a wide range of crimes against the country's internal and external security, which have caused severe disruption to public order."

"Vadi was allegedly recruited online and met Mossad – the Israeli intelligence service – officers five times in Vienna, Austria," reports say.

In particular, Iran's judiciary's news outlet Mizan has reported that the information Vadi provided was used by Israel to kill a top nuclear scientist during the June 12-day war.

Several military commanders and nuclear scientists were killed, also through Mossad sabotage operations which took place inside the country - likely through a ground asset like the dissident organization MEK.

The last several weeks have seen court-ordered executions ramp up in Iran, as authorities say they've been busting up Mossad-connected spy rings.

There was a second execution on Wednesday, involving Sunni Islamic terrorism:

Separately, Iran hanged a member of the ISIL (ISIS) group on Wednesday after he was accused of plotting sabotage, Mizan also reported.

Officials accused Mehdi Asgharzadeh of being a member of the group 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.

The trials of alleged spies on behalf of Israel appear to be taking place in rapid format, in military and judicial tribunals, sometimes convened in small rooms - and some were even hastily held while Israeli warplanes were still circling Iran's skies in June.

Surge in hangings in Tehran...