Israel underground bunker hospital preparing for worst-case scenarios
Deep below Jerusalem, Israeli doctors are preparing for the worst.
Sky News has been given exclusive access to an underground hospital where they are expanding capacity in case the current conflict becomes much worse.
In a bunker below the Herzog Medical Centre, the number of beds has been increased to 350 - with 100 on the way.
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"Because it's built to withstand both biological and chemical attacks," Dr Yehezkel Caine told Sky News as we entered the complex, "we have an airlock which is built of two separate sets of blast doors".
Beyond they have installed a whole new level of wards below the existing underground hospital, ripping out a logistics floor and installing more beds and equipment.
The bunkers would be activated should other hospitals closer to the front need evacuating.
They are planning for worst-case scenarios here like an all-out war with Hezbollah.
"The hospitals in the north will be overwhelmed with casualties and they themselves will come under fire, in which case they would have to evacuate their patients to the centre of the country, the same as we did in the first weeks of the war in the south," said Dr Caine.
He and his staff know the 7 October attack last year by Hamas and Iran's missile and drone barrage earlier this month have changed everything for the people of Israel.
"For the civilian population since the war of independence we've never been in a situation where the threat to the civilian population has been as great," he said.
Above ground, the Herzog Medical Centre continues with its peacetime specialisms.
It has Israel's largest ventilator unit, treating adults and children, but also excels in psycho-trauma treatment and geriatric rehabilitation.
Many of those suffering PTSD from the trauma in this conflict are treated here.
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If Jerusalem itself is attacked, the hospital can evacuate even the most vulnerable to the bunkers below in just a few hours.
The bunkers can be entirely sealed off for 96 hours in what's called a Noah's Ark procedure.
The Herzog drills its staff regularly. Preparing for a reality it hopes will never come. But events on the northern border are looking ominous.
Israel has launched one of its biggest bombardments yet of Lebanon's Hezbollah after multiple shelling of northern Israeli communities.
The lower-level war continues with the ever-present danger of escalation into something much bigger.
If it comes, doctors in Jerusalem's biggest underground hospital say they'll be ready.