Surgeons have found a 5cm tree growing inside a man's lungs.

They made the discovery while Artyom Sidorkin, 28, from Russia, was undergoing surgery, the Komsomolskaya Pravda reported.

He had been complaining of extreme pain in his chest and had been coughing up *lo** and his doctors suspected cancer.

"I blinked three times and thought I was seeing things," surgeon Vladimir Kamashev told the paper.

Medical staff believe Sidorkin had somehow inhaled a seed, which later sprouted inside his lung.

The spruce, which was touching the man's capillaries and causing severe pain, was removed.

"It was very painful. But to be honest I did not feel any foreign object inside me," Mr Sidorkin said.