JIANLI, China (REUTERS) - Rescuers searched a sunken cruise ship in the Yangtze River on Wednesday for more than 400 missing people, many of them elderly, but hopes of finding more survivors were fading in what could be China's worst shipping disaster in almost 70 years.

State television showed rescuers, some standing gingerly on the upturned hull of the Eastern Star, and scores of divers working through the night.

Rescuers were planning to cut a 55cm*60cm hole in the hull for frogmen to enter and conduct search and rescue work, Xinhua news agency said.

Only 14 people, including the ship's captain, have been found alive since the ship capsized in a freak tornado on Monday night with 456 people on board. Just 26 bodies have been recovered.

Rescuers have not slackened off, even though about 200 divers face difficulties such as cabin doors blocked by tables and beds. There is also the fear that rashly cutting holes in the hull could burst air pockets keeping people alive. "Although there's lots of work to do, saving people is still being put first," Transport Ministry spokesman Xu Chengguang told reporters.

But some relatives were already bracing themselves for the worst. "Yesterday I still had some hope. The boat is big and the water hadn't gone all the way in. Now, it's been more that 40 hours. I ask you, what do I have left?" said Wang Feng, a 35-year-old wedding photographer whose father was on the ship.

The ship was on an 11-day voyage upstream from the city of Nanjing, near Shanghai, to Chongqing.

While the People's Daily said the ship passed inspections by authorities in Chongqing last month, in 2013 it was investigated and held by authorities due to defects, according to documents from a local maritime watchdog.

The Nanjing Maritime Safety Administration investigated Eastern Star as part of a safety campaign into passenger ferries and tour boats and held the ship along with five other vessels, according to three documents on the bureau's website.

The documents did not give any detail on the nature of the defects related to Eastern Star but said that the issues were reported to the Chongqing maritime safety bureau.

The search area has been expanded up to 220km downstream, state television said, suggesting that many bodies could have been swept far away from where the ship foundered in the rain-swollen river.

Three of the bodies were found 50km away near Yueyang city in neighbouring Hunan province, state media said.

UNUSUALLY BAD WEATHER

Zou Luwang, who lives in a village near the river, said the government had called residents to warn of extreme weather conditions on the night the ship capsized. "I believe those who operate the boats have expertise about this, but the weather was unusually bad for these parts," he told Reuters.

Zhang Hui, a tour guide who survived the disaster, told the official Xinhua news agency that it was raining so hard, water was seeping through cabin windows, and that the ship then listed violently. "I thought, 'this isn't right', and I told my colleague, 'I think we're in trouble'. After I said that, the ship flipped over. It only took 30 seconds or a minute," Zhang said.

Li Yongjun, the captain of a freighter that passed near the Eastern Star shortly before it capsized, told Xinhua the weather was so bad he decided to anchor and wait out the storm. "The visibility was terrible, like being in fog, and the rain was interfering with the radar so you couldn't make anything out," Li said.

He said he heard a voice from the river crying, "Help!" just after 10pm, about 30 minutes after state media has said the Eastern Star capsized. "The rain was just too heavy, there was no way to mount a rescue, so I shouted over, 'swim to the bank!'," Li said.

DISTRAUGHT RELATIVES PROTEST

The captain and chief engineer have been detained by police for questioning. An initial investigation found the ship was not overloaded and had enough life vests on board.

The ship overturned "within one or two minutes", Xinhua quoted the captain as saying. He was dragged out of the water near a pier just before midnight on Monday.

Relatives of the missing, angry at what they perceive as a lack of information, have scuffled with officials in Shanghai. All of the passengers on board had booked their trips through a Shanghai-based travel agency.

About two dozen family members, some crying and others shouting "help us", marched down streets in central Shanghai on Wednesday towards the main government office, watched by a heavy contingent of police.

Premier Li Keqiang, who rushed to the scene to oversee rescue efforts, called for "regular and transparent updates" on the rescue and investigation, and said authorities must ensure adequate personnel and funding.

China's weather bureau said a tornado had buffeted the area where the ship was cruising, a freak occurrence in a country where twisters can happen but are uncommon.

Accidents of this magnitude are uncommon in China. State media said it was the worst recorded ship disaster on the Yangtze River. In 1948, the steamship Kiangya blew up on the Huangpu river, killing more than 1,000 people.