An Iranian drone which entered Israeli airspace in February was carrying explosives, it was revealed on Friday.

The attempted attack – the explosives were sufficient to cause damage, although the precise target remains unknown – represents the first direct attack by the Islamic republic on Israel.

It also indicates that Iranian aggression may be set to cause a confrontation in Syria between Tehran and Jerusalem.

“An analysis of the flightpath and operational and intelligence research performed on parts of the Iranian UAW that entered our territory on February 10 shows it carried explosive material and its mission was to carry out a destructive operation,” the Israel Defence Forces said.

“The drone’s interception by attack helicopters thwarted the attack and the Iranian intention to carry out an operation on our territory.”

Iran has long backed terror groups such as Hezbollah and Hamas, repeatedly threatened to annihilate the Jewish state and initiated terror attacks on Israeli targets around the world.

But the news about the nature of February’s drone mission suggests Iran is upping the ante. As a senior Israeli military source told the New York Times’ Thomas Friedman: “This is the first time we saw Iran do something against Israel – not by proxy. This opened a new period.”

Israeli media agreed with this characterisation. Israel’s statement on Friday “brings the confrontation” between Israel and Iran “into the open” for the first time, Channel 10 news suggested.

The drone, launched by an Iranian Revolutionary Guard unit operating from the T4 airbase near Palmyra in central Syria, was shot down 30 seconds after entering Israeli airspace on 10 February. It is believed to have been a relatively new stealth model whose design was stolen from an American unmanned aerial vehicle that was captured by Iran in 2011. Israel then proceeded to carry out a series of airstrikes against Iranian targets in Syria.

The revelation that the drone was not simply on a reconnaissance mission, but was planned to engage in a potential attack, helps explain last Monday’s significant Israeli missile strike on the T4 base. “Iran has been building a fully functional air base of its own in every respect, with only the fighter planes missing. It was the centre of Iran’s attack drone operations. It had surface-to-air missile defence systems and all manner of other protections,” according to the Times of Israel. The strike reportedly targeted Iran’s entire attack drone programme at the base.

Fourteen people, including seven Iranians, were killed in the raid (pictured). Following its usual practice, Israel did not claim responsibility for the attack – although Russia, Syria and Iran pointed the finger of blame at it. However, on Monday an Israeli military official said Israel carried out the attack; a claim which the IDF later attempted to row back.

Iran has threatened revenge. “The Zionist entity will sooner or later receive the necessary response and will regret its misdeeds,” Iran’s Foreign Ministry spokesman Bahram Qasemi told reporters on Monday.

His words were only marginally less sabre rattling than those of Ali Shirazi, the liaison for Iran’s Supreme Leader Ayatollah Ali Khamenei to the elite Quds Force. “If Israel wants to survive a few more days, it has to stop this childish game,” he said. “Iran has the capability to destroy Israel and given the excuse, Tel Aviv and Haifa will be razed to the ground.”

Hassan Nasrallah, the leader of Iran’s proxy army, Hezbollah, said that the Israeli strike on T4 was a “historic mistake”.

Israel’s military and intelligence services are said to be preparing for Iranian retaliation and apparently believes that an attack would likely be carried out by the Revolutionary Guard air force, with surface-to-surface missiles or armed drones. This would be a departure from previous clashes between Israel and Iran, in which Tehran’s reprisals were carried out through the likes of Hezbollah terrorist.

Were Iran and its proxies to follow through on these threats, Thomas Friedman speculated, “Israel may use the opportunity to make a massive counterstrike on Iran’s entire military infrastructure in Syria.” On Tuesday, Israel released images of a number of Iranian bases in Syria; a not-so-subtle threat, Israeli media suggested, of potential IDF targets if Iran does carry out reprisals. Israeli intelligence believes the sites are used by Iran for its missions in Syria, as well as to transport weapons to its proxies in the region.

That infrastructure is the result of Iranian expansionism in the region in recent years in general – analysts have identified an “arc of influence” connecting Tehran to the Mediterranean Sea and the border with Israel –  and the ayatollahs’ growing sway in Syria in particular.

According to BICOM, Iran has approximately 53,000 fighters under its control in Syria. This includes up to 10,000 Revolutionary Guards but excludes the 100,000-strong Syrian National Defence Forces, Tehran’s attempt to formally unify Assad’s local militias. Iran is also said to have established between 10-13 military bases across Syria for itself and its Shia militias (which include Afghani, Pakistani and Iraqi and Syrian troops) and is building facilities in Lebanon and Syria to manufacture accurate missiles for Hezbollah.

Publicly, Israel has made clear its intention – by military means if necessary – to maintain its “red lines” in Syria. Key among these is that it will not allow attempts to manufacture and transport “game-changing” weapons to Hezbollah (which, thanks to Iran, has an estimated 140,000 missiles pointing at Israel). The outgoing head of the Israeli air force last year stated that Israel had conducted approximately 100 airstrikes inside Syria in order to uphold these red lines in recent years.

Iran claims that its bases are designed to protect Syria from Israel. The reality is very different. As Karim Sadjadpour, senior fellow at the Carnegie Endowment and a professor at Georgetown University, hasargued: “Distilled to its essence, Tehran’s steadfast support for Assad is not driven by the geopolitical or financial interests of the Iranian nation, nor the religious convictions of the Islamic Republic, but by a visceral and seemingly inextinguishable hatred for the state of Israel.”