TEL AVIV, March 5 - Israel's campaign against Iran has entered what sources described as a second phase, in which fighter jets will strike ballistic missile facilities located deep beneath the surface, two individuals familiar with the campaign said on condition of anonymity because of the sensitivity of the operation.
The escalation follows nearly a week of coordinated air operations with the United States. Those initial strikes, the sources said, included opening salvos that killed Iran's leaders and precipitated a broader regional conflict marked by Iranian launches at Israel and targets in the Gulf and Iraq, and Israeli strikes in Lebanon.
Israeli military statements say forces have already hit hundreds of Iranian missile launchers that were positioned above ground and capable of targeting Israeli cities. The next set of operations will target bunkers and underground storage sites where ballistic missiles and their supporting equipment are kept, the two sources said.
One of the sources described a central aim of the campaign as neutralising Iran's capability to conduct aerial attacks against Israel by the end of the war, a campaign that is also concentrating on undermining the Islamic Republic's leadership.
A military spokesperson did not provide an immediate response to a request for comment about future attack plans. Earlier public statements from the military and U.S. military officials asserted that, in the opening days of the campaign, they had gained control of much of Iran's airspace.
In a statement issued on Thursday, the military said that overnight the Air Force struck "an underground infrastructure site used by the Iranian regime to store ballistic missiles and storage sites for missiles intended for use against aircraft." According to a review of public military announcements since the joint U.S.-Israeli operations began on Saturday, the armed forces had not previously declared strikes on underground missile facilities.
Estimates of the size of Iran's missile arsenal prior to the conflict vary. Israel's military has estimated roughly 2,500 missiles, while other analysts cited in the public record put the number at around 6,000. How many missiles remain available to Tehran could shape the conflict's trajectory.
Despite the strikes on launchers and infrastructure, Tehran has continued to fire missiles at Israel and across the wider region. Douglas Barrie, of the International Institute for Strategic Studies, said the think tank assesses that Iran still retains some land-attack cruise missiles - precision-guided weapons that can fly low to evade radar detection.
Officials and observers have emphasised that Israel's Air Force has flown near-constant sorties since Saturday. The tempo increased after Lebanon's Iran-backed Hezbollah fired rockets into Israel, which in turn prompted substantial Israeli airstrikes as far north as Beirut.
Sources familiar with operational details and an Israeli security official said that, in certain missions, the same Israeli warplanes struck targets in Iran or western Tehran on the outbound leg and then struck Hezbollah positions in Lebanon on the return leg, effectively combining multiple targets in a single sortie.
Israeli and U.S. officials report that ballistic missile and drone launches from Iran have fallen since Saturday. They attribute that decline in part to strikes on Iranian launch locations and associated military infrastructure by U.S. and Israeli forces. The Israeli military has also said the reduction in launches could reflect a Tehran decision to conserve missile inventories in anticipation of a prolonged war of attrition.
Eran Lerman, a former Israeli deputy national security adviser, said leaders had hoped the initial week of strikes would cause Iran's ruling system to "begin to disintegrate earlier, more quickly." He added, "But this has yet to happen and as long as it doesn’t, the system needs to be further and further degraded."
This reporting details a tactical shift from primarily above-ground engagements to operations targeting subterranean missile storage, while underlining continued uncertainty about Iran's remaining missile capabilities and the campaign's longer-term objectives.