Chinese authorities on Friday morning began preliminary work on righting a cruise liner that capsized earlier this week with 456 people aboard, saying they had given up hope of finding more survivors.

Just 14 people are known to have survived the late Monday disaster on the Yangtze River, while 77 bodies have been recovered, leaving 365 people, most retirement-age tourists, unaccounted for, state media reported.

Meanwhile, hundreds of relatives of the passengers gathered in a public square in the town of Jianli, an about 90-minute drive from the site of the disaster, clutching candles and flowers. Some knelt with tears in their eyes, Reuters news agency reported.

"We just want an early resolution to this tragedy,"one woman told Reuters as she sobbed. "We feel so devastated."

About 200 divers had been working round-the-clock to search for survivors, but muddy water, strong current and debris piled up inside the boat have made their job extremely tough.

Other rescue workers had cut into the hull on Wednesday to find anyone who might have been sheltering in air pockets. But more than 24 hours since the last survivors were brought out alive, China's Transport Ministry said crews would begin turning the boat Friday morning.

Despite an extensive search and the deployment of sensitive scanning devices, "no sign of life was found," Transport Ministry spokesman Xu Chengguang said at a news conference. "In general, it can be judged that there is no possibility of more survivors. Therefore, we can turn the boat."

"Turning the boat will make it easier to bring the bodies out," said Gong Yongjun, a professor specializing in rescue and salvage at the Transportation Equipment and Ocean Engineering College in the northeastern city of Dalian. "It would be very dangerous to turn the boat with lives inside."

China has promised that there will be no "cover-up" in the investigation into why the Eastern Star capsized suddenly in stormy weather Monday while on an 11-day cruise up Asia's longest river.

But anger has been rising among relatives of those on board, largelyata lack of information and access to the site.

"At the moment we know absolutely nothing," Alex Chu, the son-in-law of a passenger, told CNN. "We want to go to the site, but we can't. We want to see the latest developments, but they tell us it looks the same on TV."

Some relatives have questioned why the boat carried on upriver in the teeth of a storm, when at least three other boats dropped anchor. Others asked why the captain and several crew members apparently had time to put on lifejackets buthad not been able to send a distress call.

It's also unclear whether the Eastern Star was sufficiently stable to withstand adverse weather conditions.

It is unusual for a ship to capsize so quickly, and investigators will examine "why the ship's stability failed so catastrophically," said Lawrence Brennan, a maritime law expert at Fordham Law School in New York.

Investigators could study factors such as proper crew training, and whether they had received a warning about impending bad weather, he said.

On Thursday morning, Chinese President Xi Jinping and other senior Communist Party leaders called on rescuers to "take all possible measures" to find survivors.

The Politburo Standing Committee also "noted the importance of caring for passengers' families" and promised "timely, accurate and transparent" information from the investigation, the official Xinhua News Agency reported.

However, restrictions have been placed on domestic and foreign reporting at the scene, and local media were ordered not to deviate from the official line.

On Wednesday night, frustrated at their lack of access, dozens of relatives broke through a police cordon and marched several miles to the river.