Ship China
Sun Zhenglong was rescued after a shipwreck and was kept as a slave by his saviors for three years.Reuters

A Chinese fisherman has managed to escape from a ship where he was kept as a slave for three years, after being rescued from a shipwreck, the Mail Online has reported.

Sun Zhenglong, 41, fell from his own fishing vessel in 2011.

The boat had departed from Lianyungang, a city in the east of China.

"I thought at first that my colleagues would see me but they didn't," Sun said. "I watched the boat and its lights disappear and then I was alone.

"It was cold and dark and there was absolutely nothing in sight, and after 12 hours I was convinced I was going to die."

Sun, however, was rescued by some men who had spotted him in the water.

"II couldn't believe it when another boat came past early in the morning and I managed to shout and waved my hand, and they saw me."

After being rescued by the men, Sun was forced to repay his saviours by working unpaid for the crew.

He said the skipper of the rescue boat turned out to be a cruel man who demanded payment for saving him. When Sun said he had no money he replied: "Then you will work off your debt to me."

Each time the captain and the crew went ashore they would keep him chained up, Sun explained.

His wife Ding, 38, held a funeral service believing he had died in the sea.

Sun was forced to work hard and long hours; he was fed only on scraps and was kept locked up in chains in the bowels of the ship.

"I had to do everything they told me to do. The only thing I asked in return was that they inform my family I was still alive - I begged them.

"I lost all track of time. I had no mobile phone. Sometimes I was locked aboard the boat for two weeks at a time, all alone," Sun continued. "Only the sound of firecrackers on the shore told me the time as I could guess that, for example, the spring festival was underway."

After three years of slavery, Sun decided to escape.

While the ship's nets were cast some six hours out of port, he dived into the ocean and began swimming for the shore.

""They used to watch me like a hawk every time we were near the shore, but I think they got complacent and thought they had just broken my will to escape," Sun said.

"I stopped asking about when I might be free or if there was any news of my wife. I knew it was a risk but I didn't care whether I lived or died, I wanted either as a free man."

Dehydrated and exhausted, Sun eventually reached the shore where he was spotted by two hikers who raised an alarm.

Sun was rushed to hospital and released after 24 hours.

He was then allowed to telephone his wife.

"I never could think I would meet my husband again, even in a dream. Thank goodness he has come back to us," said his wife Ding.

Police are hunting for the crew which kept Sun as a slave.

The only information Sun could give was that they all spoke with southern Chinese accents.