A financial adviser has barely escaped with his life after being beaten and held hostage for four days by a gang of old-age pensioners.

American James Amburn was beaten until his ribs broke, burnt with cigarettes and hit with a Zimmer frame by the gang of five pensioners furious that he'd lost their £2 million ($4.1 million) savings.

Living in Germany, Mr Amburn was ambushed as he left a cafe and driven in the boot of an Audi to a house, where he was dumped in a cellar.

"I was jumped from the rear and struck," he told UK tabloid The Sun.

"Then they bound me like a mummy with masking tape. It took them quite a while because they ran out of breath."

In four days, the pensioners fed him just two bowls of soup, burned him with cigarettes and threatened to kill him "again and again", angry that he had invested their money in a failed Florida property scheme.

He escaped once but was recaptured and beaten until his ribs broke.

Mr Amburn was eventually rescued after convincing his captors to let him fax a Swiss bank in an attempt to get their money.

He left a note for police at the bottom of the fax and armed cops stormed the house in Bavaria on Saturday.