Two British Royal Air Force Hercules aircraft have returned to Malta after rescuing workers deep in the Libyan desert, the British Defence Secretary has said.

Liam Fox said the planes picked up 150 workers, including many Britons and workers of other nationalities.

He did not say whether the flights were authorised by the Libyan authorities. The Press Association said the operation was carried out by Special Forces.

Security correspondent Frank Gardner told the BBC however, that the operation appeared to have been carried out without cooperation from the Gaddafi regime.

The operation, he added, was extremely complex.

"It was not just oil workers in one camp - they had to deal with several different locations and a number of heavily armed people."

Peter Dingle from Lancashire was among those airlifted out in the military operation.

"We found out early this morning that the Hercules was coming in but everything was being kept quiet," he told BBC Radio 5 live.

"We couldn't send e-mails out to any people or anything like that because obviously the media would find out that the British military was coming."

It is not known if there were Maltese among them. However the planes went to an area south of Benghazi, whereas most of the Maltese still in Libya are in the Tripoli area and south of the capital. A Maltese flight to pick up workers from the desert south of Tripoli was authorised by the Libyan authorities yesterday.

Meanwhile, HMS Cumberland, which brought 250 Britons to Malta last night, is now half way back to Benghazi. Another frigate, HMS York, is in Grand Harbour taking provisions before also heading south during the night.