Rescue workers have retrieved dozens of bodies from the capsized Eastern Star cruise ship as any hope of finding more survivors fades.
Fourteen people are known to have survived the sinking of the ship on Monday night during a heavy storm on the Yangtze River.
Sixty-five bodies have been recovered, state media reported on Thursday. More than 370 people are missing.
Rescuers began cutting their way into the capsized Eastern Star cruise ship last night, but the work was suspended on Thursday due to persistent bad weather that has hampered the rescue effort from the start.
The passenger ship was carrying 456 people when it capsized on the Jianli section of the river in Hubei province.
Watch: Survivors from China's Yangtze river boat disaster are treated in hospital
The upturned ship had been surrounded by three large salvage vessels and two more were on their way, state media reported yesterday.
Professor You Qinghua, from Shanghai Maritime University, said there was only a "slim" chance that any of the missing could have survived.
"The survivors rescued from the ship [on Tuesday] already said they felt breathless," he said. "People can survive after being trapped in debris for 72 hours following an earthquake. But there is no way people could hang in there in a capsized ship for that long."
READ MORE: Close calls with tragedy on the Yangtze River
About 80 family members, frustrated by the paucity of information coming from authorities, hired a bus to make the eight-hour journey from Nanjing to Jianli county in Hubei, where the ship sank.
The protesters later broke through a cordon of 20-25 paramilitary police who had tried to stop them at a roadblock.
Early on Thursday, the deputy police chief of Jiangsu province, of which Nanjing is the capital, told the relatives they could go to the disaster site only in the daytime.
He promised to arrange buses for them to view the boat in the morning, but said journalists were barred from the trip.
The search-and-rescue mission would continue and another 180 divers had been sent to join the 183 already on site, a transport ministry spokesman said yesterday.
Chen Xiang was among the first batch of divers. The diver from the PLA Navy's South Sea Fleet said low visibility underwater hindered the search.
"I could not see anything and could rely only on touch," Chen said. "The water was muddy, and the current was strong. It was dark and cold."
Chen said it took him 15 minutes before he could reach the second deck of the ship. Something heavy and sharp hit him on the shoulder as he tried to enter a room, forcing him to give up his search.
Staff at a Jianli funeral parlour had prepared "a large number" of coffins, local official newspaper Changjiang Daily reported.
Premier Li Keqiang bowed in silent tribute to the dead as he arrived at the scene of the rescue yesterday morning.
Questions remain over why the ship made a sudden turn 10 minutes before capsizing and whether a tornado recorded in the area at the time of the accident had directly hit the ship.
The ship's captain and chief engineer, who both survived, are in police custody.
"If the voyage data recorder [the black box of the ship] shows the captain made the turn in the stormy weather instead of losing control [after the ship was hit by strong winds and tides], it would be fair to say he bears responsibility for the tragedy," You said.
Chen Yuanjian, a director of the ship's operator, a Chongqing company called Dongfang, admitted the ship's structure had been modified.
He said this was done only to meet updated standards from the shipping authorities, news website The Paper reported.
Chen Yiylong, a captain from the company, said he did not believe the captain of the Eastern Star would have abandoned his passengers to escape.
The owner of the ship that capsized has been ordered to suspend operations of a second boat and carry out safety probes on its entire fleet.
An official at the Changjiang River Administration of Navigational Affairs said the Chongqing Eastern Shipping Corporation would need to halt operations of its Eastern Pearl ship, which was built to the same design as the Eastern Star.
"We’ve already ordered the Oriental Pearl to come to dock and instructed the crew and passengers to leave the boat," the official, who was part of the emergency response unit, said.
Other boats in the fleet could still operate, but the company would have to send teams of experts aboard to carry out checks.
A senior manager at Chongqing Eastern Shipping Corporation declined to comment.
The Eastern Star had passed inspections by the authorities in Chongqing last month, the People’s Daily said.
But according to documents from a local maritime watchdog, it was held by authorities due to defects in 2013.
The Nanjing Maritime Safety Administration had investigated the 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 gave no details of the defects, but said the issues were reported to the Chongqing maritime safety bureau.
Xinhua reported that all boat operators on the Yangtze river should prepare for the impending flood season, pay close attention to the weather and improve their emergency response measures.
Additional reporting by Reuters, Agence France-Presse