Only 14 survivors, one of them the captain, have been found after the ship carrying 456 overturned in a freak tornado on Monday night in Jianli in Hubei province. Most of the passengers were elderly tourists.

The four-storied ship was righted and raised on Friday, allowing rescuers onto it to clear away debris, break down cabin doors and look for the remaining missing. The river is being swept to as far away as Shanghai looking for the missing.

Government spokesman Hu Kaihong told reporters that DNA tests were being carried out to identify the bodies.

Sunday marks seven days since the Eastern Star went down, and according to Chinese tradition this a key date on which to mourn the dead.

State television showed rescue workers and government officials standing on a barge facing the Eastern Star, removing their hats and bowing their heads, as surrounding boats sounded their horns.

Families members will also gather near the river for ceremonies.

More than 1,400 relatives have come to Jianli, with many expressing frustration at the lack of information from the government. On Friday, one burst into a just-concluded news conference, publicly accusing the government of treating its people like enemies.

The government says that it is doing everything possible to help the relatives, including providing free accommodation and medical services, and Vice Premier Ma Kai has been dispatched to meet family members personally.

Officials organized for foreign reporters and sat in on an interview with some relatives, who praised the government's efforts.

"It made me feel incredibly warm. When he shook my hand and said a few words to me, told us to keep on going. I felt that he didn't seem like a political leader at all. He was so genial. He was like my own father," Wang Hua, 42, who lost both parents on the ship, told Reuters of her meeting with Ma.

Major state newspapers on Sunday carried the same lengthy story by the official Xinhua news agency on their front pages, headlined "Bearing great responsibility to the people" and detailing the government's efforts.

"In the midst of disaster, we are all of one heart, the whole nation helping each other, staunchly moving forward," it wrote.

The company which operated the ship has apologized for the disaster and said it would "fully" cooperate with the investigation. Beijing has pledged there would be "no cover-up".

Police have detained the captain and chief engineer for questioning as part of the investigation. An initial probe found the ship was not overloaded and had enough life vests on board.

The disaster has now caused a higher toll than the sinking of a ferry in South Korea in April 2014 that killed 304 people, most of them children on a school trip. It is China's worst shipping catastrophe in seven decades.