Pro-Palestinian activists broke into a Royal Air Force base in central England on Friday, damaging and spraying red paint over two planes used for refueling and transport.
Palestine Action said two members had entered the Brize Norton base in Oxfordshire, putting paint into the engines of the Voyager aircraft and further damaging them with crowbars.
"Despite publicly condemning the Israeli government, Britain continues to send military cargo, fly spy planes over Gaza, and refuel US/Israeli fighter jets," the group said in a statement, posting a video of the incident on X/Twitter.
"Britain isn’t just complicit, it’s an active participant in the Gaza genocide and war crimes across the Middle East."
Prime Minister Keir Starmer condemned the "vandalism" as "disgraceful" in a post on X/Twitter.
"It is our responsibility to support those who defend us," the defense ministry said.
A spokesperson for Starmer said the government was reviewing security across all British defense sites.
'Armed Forces represent Britain's best'
"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 is an inspiration to us all," it said.
"It is our responsibility to support those who defend us."
Police said they were investigating a report of people gaining access to the air base and causing criminal damage.
Palestine Action is among groups that have regularly targeted defense firms and other companies in Britain linked to Israel since the start of the conflict in Gaza.
The group said it had also sprayed paint on the runway and left a Palestine flag there.
British Defense Minister John Healey ordered an investigation and a review of wider security at the country's military bases.
"The vandalism of RAF planes is totally unacceptable," Healey said on social media platform X, following the incident in central England.
"I am really disturbed that this happened and have ordered an investigation and a review of wider security at our bases."