BEIHAI (China) • In the darkness of the tropical waters of the South China Sea, the shabby, blue-hulled Chinese fishing trawler edged closer to what was almost certain arrest for Mr Zhang Deren, the boat's engineer. He was a very long way from his home here in southern China.

Earlier that day, the Indonesian maritime police had boarded his boat, accusing the crew of fishing illegally in Indonesian waters. After the rest of the crew was ordered onto their vessel, the Indonesians instructed Mr Zhang, a 53-year-old with a weather-beaten face, to follow in the trawler.

At 2am, after a 12-hour journey to the Indonesian shore, help arrived. A Chinese coast guard vessel, as big as a naval frigate, pulled alongside Mr Zhang's boat. The coast guard ship then rammed it, separating it from the Indonesian escort.

"At that moment, I knew I was out of trouble," he said. He shared his story with The New York Times after a week-long voyage back to his home port here on the Gulf of Tonkin, close to Vietnam.

Indonesia's furious reaction - and the resulting diplomatic spat with Beijing that erupted late last month - is the latest sign of growing frustration with China over territorial rights in the South China Sea.

South-east Asian nations are also angry that China's fishing armada, supported by its vigilant coast guard, is plying waters that offer diminishing stocks of fish. Most of the disputes are inside the so-called nine dashes, an area drawn by China in the 1940s that covers more than 80 per cent of the South China Sea, though it is not recognised by international law.

Back home, Mr Zhang has been called the "lucky fisherman" who got away, reported The New York Times.

He talked about his ordeal from the docks in Beihai, where fishing vessels that travel all over the South China Sea bring back their hauls, including stingray, baby shark and squid.

Mr Zhang recalled that as the noon-time sun was beating down on the fishing boat, and the crew was on deck cleaning the fishing nets, someone called, "A gunboat is coming".

"It took them about 30 minutes to get near," he said. "I heard two shots - 'pa, pa' - and the sound of their vessel knocking against our ship. Their boat was too small to crash into a large ship like ours. Soon I heard more intensified shooting."

Three Indonesians in dark green camouflage and helmets boarded the trawler and told the members of the crew to squat with their hands on their heads, Mr Zhang said. They were ordered onto the Indonesian boat, but soon he and the captain were ordered back to their vessel to turn on the engines.

By that time, he said, the captain had alerted the Chinese coast guard of their predicament.

With the three Indonesians still on board, Mr Zhang said, he drove the boat at less than maximum speed hoping the coast guard would rescue them before they reached Indonesia.

He was sleeping when the captain yelled that the Chinese coast guard had arrived.

"The Chinese coast guard vessel was huge," Mr Zhang told The New York Times. "They were more than twice our size. They announced over a loudspeaker: 'This is the Chinese coast guard.'"

When the coast guard cutter rammed the trawler to free it, the Indonesian police officers who had remained aboard with Mr Zhang revved up the engines to try to get away.

In the commotion, one of the engines almost ran out of oil, sending up clouds of white smoke. The Indonesians fled, taking the Chinese captain with them and leaving Mr Zhang to fix the engine, reported The New York Times.

The Chinese coast guard called out to him: "Can you drive the boat?" Mr Zhang said, "So-so." The two vessels then travelled together for about a week back to Beihai.

When asked if the trawler had been fishing in Indonesian territorial waters, Mr Zhang said: "I'm not quite sure. I'm only an engineer." Then he added with a laugh: "But it is probable."

At the dock, the boat owner's, Mr Chen Jifa, said he was confident the Chinese government had the power to arrange the return of the detained crew.

Indonesia's Maritime Affairs and Fisheries Minister Susi Pudjiastuti said on April 1 that the captain of the Chinese fishing boat will be charged with poaching, along with his chief engineer and fishing master.

The remaining five of the eight Chinese nationals arrested by Indonesian maritime authorities will be deported, she said.

Ms Susi has demanded that Beijing return the Kway Fey fishing vessel to Indonesia so that she can sink it - to send a strong signal to poachers.