An aerial map from 2004 showing Iran’s clandestine nuclear activities at the Parchin military complex near Tehran. Photo: isis-online.

A huge explosion that struck just outside Tehran last week was the result of an Israeli cyberattack, a US-based security expert said over the weekend.

The explosion occurred at the Khojir military site east of Tehran, which was used for weapons manufacturing. According to Reuters, it was also a nuclear weapons research facility in the past.

Theodore Karasik, a senior adviser at Gulf State Analytics, said, “Although military and defense industry accidents do occur in Iran, the consensus appears to be a cyberstrike by Israel against Iran.”

“The ongoing cyberwar between Iran and Israel is not new,” he said, noting an April cyberattack on Israel’s water system, widely attributed to Iran, followed by a much bigger retaliatory attack that temporarily shut down a major Iranian port.

“To be sure, the timing of the explosion is important given continued Iranian mischief in the region,” he added. “As these tensions will probably grow in the coming months, the tit-for-tat nature of cyberwar is part of a troubled security landscape.”

“The Khojir event is a continuation of the Stuxnet virus used 10 years ago to disrupt and deter Tehran’s military industry,” he said.

The explosion at Khojir took place in the early hours of Friday, the Wall Street Journal reported. The Iranian Defense Ministry said the blast was caused by an explosion in an industrial gas tank in a civilian area of Parchin. According to Iranian government spokespeople the blast caused no casualties.