Mr. Chen said he had no information about his brother’s disappearance. But he had spoken to the relatives of one of the other missing volunteers, Cai Wei, who said that Mr. Cai and his girlfriend had been detained and accused of “picking quarrels and provoking trouble,” a vague charge that the government often uses against dissidents.
Reached by telephone on Tuesday, an employee at a police station in the Beijing district where Chen Mei lives said he was unclear about the case. The group’s site on GitHub, a platform popular with coders, is now blocked in China.
Volunteers for similar online projects have also been questioned by the authorities in recent days. In blog posts and private messages, members of such communities have warned each other to scrub their computers. The organizers of another GitHub project, 2019ncovmemory, which also republished censored material about the outbreak, have set their archive to private.
