The massive explosion near Tehran on Saturday that killed 17 Iranian Revolutionary Guard members, including the architect of Iran's missile program, could be the latest strike in a covert war on Iran's nuclear program, the British newspaper the Guardian reported on Monday, as speculation grew among the media that Israel’s Mossad may have been behind the blast.

While the Revolutionary Guard claimed on Sunday that the explosion was an accident and occurred while military personnel were transporting munitions, the Guardian spoke to a source closely tied to the Iranian regime who pointed a finger at the Mossad.

"I believe that Saturday's explosion was part of the covert war against Iran, led by Israel," the source, a former director of an Iranian state-run organization told the Guardian, on condition of anonymity.

Get the Israel Hayom newsletter sent to your mailbox!

The source recalled a blast at a missile base near the Iranian city of Khorramabad in October 2010 that was similar to Saturday's incident. During that explosion, at least 27 soldiers were killed. Iranian authorities claimed they had been transporting ammunition at the base. Then, too, the regime denied any hints of foreign sabotage aimed at damaging Iran's nuclear facilities.

However, the Iranian source told the Guardian, "I have information that both these incidents were the work of sabotage by agents of Israel, aimed at halting Iran's missile program."

The source's comments echo other recent reports on possible Israeli involvement in Saturday's explosion near Tehran. TIME magazine on Sunday quoted a Western intelligence official as also saying the Mossad was responsible for the blast.

"Don't believe the Iranians that it was an accident," the official said. He added that other sabotage attacks were being planned to hinder Iran's plans to develop nuclear weapons. "There are more bullets in the magazine," the official said.

Richard Silverstein, an American blogger who covers the Arab-Israeli conflict and Jewish-Muslim relations, first suggested an Israeli link to the Iranian explosion on Saturday. Silverstein claimed that an Israeli official "with extensive political and military experience" personally provided him with exclusive information according to which the Mossad and Iranian opposition group Mujahedin Khalq were responsible for the explosion on the Iranian base. Silverstein wrote that intelligence groups throughout the world are aware of Israeli-Khalq collaboration.

Claims of Israeli intelligence involvement in Saturday's explosion in Iran follow chatter by Israeli politicians and media over a possible military attack on Iran's nuclear facilities before the release of the International Atomic Energy Agency report last week on Iran's nuclear program. The Vienna-based U.N. nuclear watchdog said that Iran had been secretly developing nuclear weapons since 2003. Citing "credible" information from member states and elsewhere, the agency listed a series of activities tied to developing nuclear weapons, such as high explosives testing, the development of nuclear warheads for missiles and the development of an atomic bomb trigger.

"A military strike on Iran is growing more likely than the diplomatic option," President Shimon Peres told Israel Hayom just before the report's publication, adding that, "Iran threatens not only Israel. What needs to be done must be done and there is a long list of options."

However, speculation about the Mossad's participation in last weekend's Iranian explosion is raising questions about the possibility of a shadow war being waged against Iran, in which covert actions have replaced the option of an overt military strike.

"If Israel -- perhaps in concert with Washington and other allies -- can continue to inflict damage to the Iranian nuclear effort through covert actions, the need diminishes for overt, incendiary moves like air strikes," Sunday's TIME report said. It referred to the Stuxnet computer worm, which scientists and experts have linked to Israel and the U.S., as just one of many international covert activities in recent years that have damaged Iran's uranium enrichment facilities.

Other mysterious activities in the last few years include explosions at different Iranian missile bases and nuclear sites, and assassinations of Iranian scientists believed to be involved in the development of the country's nuclear program.

Suggestions of a covert war against Iran may have been further strengthened by the Revolutionary Guard's revelation on Sunday that a key figure in the development of Iran's missile program, Gen. Hasan Moghaddam, was killed in the blast.

As the 17 Iranian Revolutionary Guard members killed in the incident were laid to rest in Tehran on Monday, several officials from the regime's leadership, including Supreme Leader Ayatollah Ali Khamenei, attended Moghaddam's funeral, testifying to his important position in the Revolutionary Guard.

Hossein Salami, the deputy commander of the guard, described Moghaddam as "the main architect of the Revolutionary Guards' cannon and missile power and the founder of the deterrent power of our country."

While theories continue to abound about Saturday's blast near Tehran, French Foreign Minister Alain Juppe on Monday warned against a military strike on Iranian nuclear facilities, saying this would drag the world into an "uncontrollable spiral."

"I think we have to do everything we can to avoid the irreparable damage that military action would cause," Juppe told RTL radio. "France's position is firm: If we need to reinforce sanctions, we are ready." He noted that the EU would cancel loans from the European Investment Bank to Iran.

U.S. President Barack Obama reiterated on Monday that all options were on the table on Iran's nuclear ambitions. "When I came into office the world was divided and Iran was unified around its nuclear program. We now we have a situation where the world is united and Iran is isolated," Obama said at news conference in Hawaii on Sunday.

Obama stressed that China and Russia, who formally oppose an increase of pressure on Iran, were firm in their position that sanctions on the country would work. "All three of us entirely agree on the objective, which is making sure that Iran does not weaponize nuclear power and that we don't trigger a nuclear arms race in region," Obama said.

Meanwhile, a South Korean diplomatic source said on Monday that "hundreds of North Korean scientists and technicians have been employed at more than 10 nuclear sites and missile facilities in Iran." The official claimed "this collaboration has gone on for years." Another report suggested that some scientists from Pyongyang were at the site of Saturday's explosion near Tehran.

The Iranian parliament, meanwhile, approved new legislation on Monday to sharply increase punishments for Iranian citizens who visit Israel. The new legislation stipulates that any citizen who travels to Israel will be sentenced to two to five years in prison, and will also be prohibited from holding a passport for three to five years, the official Iranian IRNA news agency reported.

Like our newsletter? 'Like' our Facebook page!