Terrified Brits are trying to get out of Cyprus after realising the UK used an airbase there to launch strikes on Syria.
Politicians on the Mediterranean island are also outraged, calling for the "anachronism" to be removed.
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Cyprus lies a few hundred kilometres to the west of Syria, where the US, UK and France launched strikes against suspected chemical weapons facilities over the weekend.
The UK planes took off from Cyprus, where the UK has two Royal Air Force outposts. The Tornado bomber jets travel so fast, it took them only two hours to take off, hit their targets and return.
British media reports UK nationals are trying to leave the island, and those who had trips planned there are cancelling and finding other places to go.
"We are confident the Russians won't try to attack but we do have a contingency plan to get people out," a defence source told The Daily Express, which reports around 25,000 Brits live on Cyprus.
The UK didn't inform the Cypriot government of the strikes ahead of time.
"What the British authorities decide to do on the sovereign bases is not within the control of the Republic of Cyprus," government spokesman Prodromos Prodromou said.
The Guardian reports this may have been because there is a strong Russian presence on Cyprus too - around 40,000 Russians live there, and the island has strong economic ties to Moscow.
Hundreds of local Cypriots protested the strikes, many of them from the local Communist Party according to reports.
"We do not want Cyprus to be involved in any military operation and that includes using the British bases as a launching pad for strikes against Syria," said Stefanos Stefanou, spokesman of opposition party Akel.
"In our view the bases are an anachronism and their role should be raised with the British government."
One sign carried by the protesters read "NATO killers go home."