BEIJING — Grieving relatives of the hundreds of people who died in the Yangtze River cruise ship disaster expressed growing frustration on Friday at the lack of answers from officials over why the boat capsized during a storm and at the government’s attempts to muzzle their outrage.

Roughly 1,200 relatives of the missing have gathered in Jianli, the city closest to where the Oriental Star capsized this week with 456 people aboard. During a news conference on Friday, several distraught family members burst into the room and demanded to speak to reporters before being ushered out by officials.

A number of victims’ relatives have described being trailed by government minders and instructed not to speak to journalists. And in a letter that family members distributed to reporters and that was posted online Friday by Phoenix News, based in Hong Kong, the relatives demanded that the bodies of victims be returned to them so they could be buried at home, rather than be cremated as rumored.

“We hope the bodies of our kin can be returned to us,” said the letter, which was later deleted online.