WATCH: Pentagon reveals test footage of bunker-buster bombs used in Iran strike

US Defence Secretary Pete Hegseth and Chairman of the Joint Chiefs of Staff Dan Caine have described in great detail the planning and execution of the US strikes on Iranian nuclear facilities.

Mr Caine shared dramatic test footage on Thursday morning (local time) showing how 30,000-pound (13,600kg) bunker-buster bombs work, such as the ones used against Iran’s Fordow uranium enrichment plant.

The video showed a GBU-57 series Massive Ordnance Penetrator (MOP) striking its target, triggering a towering cloud of dust moments before a blinding explosion illuminated the shaft during a test detonation.

According to Mr Caine, the pilots who dropped the bunker-buster bombs on the site called the blast “the brightest explosion” that “literally looked like daylight.”

The MOPs used in the attack, which can only be dropped by a B-2 stealth bomber, were manufactured in 2009 after the US learned of the existence of the Fordow site.

“Unlike a normal surface bomb, you won’t see an impact crater because they’re designed to deeply bury and then function,” Mr Caine explained to reporters during a press briefing.

“All six weapons at each vent at Fordow went exactly where they were intended to go.”

Another angle presented during the briefing showed an MOP impacting its target in slow motion, slicing through the curved interior of a second ventilation shaft without exploding as it continued to penetrate deeper into the test facility.

“A bomb has three effects that cause damage: blast, fragmentation, and overpressure,” Mr Caine added.

“In this case, the primary kill mechanisms in the mission space were a mix of overpressure and blast.”

“Imagine what this looks like six times over.”

Sharing some more detail about the strike on Fordow, Mr Caine said, “The weapons were built, tested and loaded properly” before “being released on speed and on parameters.”

He added that, “the weapons all guided to their intended targets and to their intended aim points,” before exploding.