Pro-Palestinian activists have broken into RAF Brize Norton and sprayed two military planes with red paint.
The Ministry of Defence strongly condemned the "vandalism of Royal Air Force assets" and said it was working closely with the police.
Footage posted online by Palestine Action on Friday shows two people inside the Oxfordshire airbase in darkness, with one riding on a scooter up to the Airbus Voyager air-to-air refuelling tankers and appearing to spray paint into its jet engine.
The group said the activists were able to "evade security" and claimed they had put the supply planes "out of service".
Speaking before the details were confirmed, cabinet minister Lisa Nandy told the BBC the break-in was "deeply concerning" and that the government would be "cracking down" on people who "think they can treat national security with that level of disregard".
In a statement, a Palestine Action spokesperson said: "Despite publicly condemning the Israeli government, Britain continues to send military cargo, fly spy planes over Gaza and refuel US and Israeli fighter jets."
RAF Brize Norton serves as the hub for UK strategic air transport and refuelling, including flights to RAF Akrotiri in Cyprus. The air force has conducted reconnaissance flights over Gaza out of the Cyprus base.
Palestine Action has engaged in similar activity since the start of the current war in Gaza, predominantly targeting arms companies. In May, it claimed responsibility for the daubing of a US military plane in Ireland.
The group said the activists who entered RAF Brize Norton used repurposed fire extinguishers to spray red paint into the planes' engines.
It also said they caused "further damage" using crowbars - though this is not visible in the bodycam footage it provided.
Video shows the activists then roaming freely around the airbase.
An MoD spokeswoman said: "Our armed forces represent the very best of Britain. They put their lives on the line for us, and their display of duty, dedication and selfless personal sacrifice are an inspiration to us all.
"It is our responsibility to support those who defend us."
Lord West, Labour minister for UK security and former head of the Royal Navy, said he was not aware of the details but that the break-in was "extremely worrying".
"We can't allow thing like this to happen at all," he told BBC Radio 4's Today programme, adding that breaches like it were "really a problem" for national security.
Shadow armed forces minister Mark Francois told the BBC that any attempt to interfere with the engines of large aircraft was "totally reprehensible".
He added there were "serious questions for the MoD to answer" about how protestors were able to "gain access to what is supposed to be a secure RAF airbase".
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