Chinese authorities have formally arrested at least 17 people in connection with public attempts to mark the 25th anniversary of the military crackdown on pro-democracy protests in Tiananmen Square, rights groups said, including seven people from the central city of Zhengzhou who held a public memorial event. In Zhengzhou, the provincial capital of Henan province, activist Chen Wei was formally arrested alongside her husband Yu Shiwen and three others who attended: Hou Shuai, Fang Hongwei, and Dong Guangping. Two lawyers hired by those arrested, Chang Boyang and Ji Laisong, were also formally held. All seven are were arrested on Thursday on charges of "picking quarrels and stirring up trouble," and are being held in the Zhengzhou No. 3 Detention Center, the overseas-based Chinese Human Rights Defenders (CHRD) said. "A lawyer went with us[to the detention center] today...and called up police...who said seven people had been formally arrested," Chang's daughter Chang Ruoxi told RFA on Friday. "I went with my mother and Dong Guangping's wife." "The prosecution told us[on Monday] that the crime had been changed from disrupting public order to picking quarrels and stirring up trouble," Chang said. "The other relatives confirmed[that seven people were formally arrested]." "They have been in detention for 37 days, and the authorities should have informed the family by now. They have acted illegally from start to finish." "I think this is disgraceful," she said. "All of these people are innocent." A further 10 people have been formally arrested in connection with events linked to this year's anniversary, according to CHRD, which collates and publishes reports from a number of independent rights groups inside China. Journalist Shi Yu and another memorial attendee Shao Shengdong have been released on bail, pending further investigation, the group said in an e-mailed statement on Friday. Shi's lawyer Ma Lianshun said the charges against his client were trumped up at random. "The charges against those seven people should be 'pissing off the government,'" Ma said. "They are randomly coming up with charges to pin on them. They do whatever they like." "[The government's] actions are in serious breach of the law," he said. Confirmed Zhu Xiaoding, a second lawyer hired by Shi, later confirmed his and Shao's release on bail. "That's correct. I was told by the prosecutor's office that Shi Yu and Shao Shengdong were released and that the other seven were formally arrested," Zhu said. In addition to those formally arrested, which usually signifies that a case is likely to proceed to trial, more than 50 have been put under criminal detention on public order charges before and since the anniversary. In China, charges must be specified if a person is held under criminal detention, but police are increasingly using it as a way to target dissidents and activist around sensitive political dates. Some cases are taken to trial, while in others, police may require detainees to sign pledges not to engage in further activism before releasing them on bail, under an ongoing threat of re-detention at any time. Authorities have detained dozens of activists, lawyers, academics and journalists before the 25th anniversary of the Tiananmen Square bloodshed, and tightened controls on dissent, free speech and the Internet. Many of those who were placed under house arrest or taken on enforced "vacations" were later released, Face charges while others face trial on public order charges similar to those the Zhengzhou seven are accused of. However, the ruling Chinese Communist Party bans public memorials marking the event, although police have escorted the relatives of those who died from house arrest to cemeteries to pay their respects to loved ones in private. The party has continued to ignore growing calls in China and overseas for a reappraisal of the 1989 student protests, which it once styled a "counterrevolutionary rebellion." The number of people killed when PLA tanks and troops entered Beijing on the night of June 3-4, 1989 remains a mystery. Beijing authorities once put the death toll at "nearly 300," but the central government, which labelled the six weeks of pro-democracy protests a "counterrevolutionary uprising," has not issued an official toll or list of names.