Chinese police have detained a human rights lawyer who called for the release of activists arrested for demanding that government officials disclose their assets, a lawyer said Wednesday.

Xu Zhiyong, a lecturer at a Beijing university, was held by police on Tuesday for "disturbing order in a public place", his friend and fellow lawyer Teng Biao wrote on a Twitter account.

Rights groups called Xu's arrest the latest episode in a crackdown on political activists launched after President Xi Jinping was formally appointed in March.

At least 24 activists have been detained since late March, US-based advocacy group Chinese Human Rights Defenders said in a statement.

Chinese citizens are regularly scandalised by reports of corrupt officials living lavish lifestyles, leading to calls for laws requiring government officials to publicly list their assets.

Bloomberg news agency last year reported that Xi's family had assets worth $376 million, while the New York Times reported that relatives of former Premier Wen Jiabao had controlled assets worth $2.7 billion.

A co-ordinated crackdown was "targeting a loose grouping of activists... who have peacefully advocated for democratic and rule-of-law reforms, constitutionalism, human rights and social justice", Chinese Human Rights Defenders said.

Three anti-corruption activists detained in April in the central province of Jiangxi are awaiting trial on charges of illegal assembly, which carry a maximum sentence of five years in prison, lawyer Zheng Jianwei told AFP.

Xu signed an open letter in April calling for them and other activists seeking assets disclosure to be released, US-based advocacy group Human Rights in China said in a statement.

Xu, a prominent lawyer and advocate of legal reform, was arrested in 2009 on tax evasion charges, which were dropped following condemnation by rights groups.

Teng Biao could not be reached for comment on Wednesday, after writing on Twitter that his phone had been disabled.

President Xi has vowed to crack down on all forms of corruption, saying it threatens the future of the ruling Communist Party.

Anger as China law expert defends rape of bar hostess
Beijing (AFP) July 17, 2013 - A legal expert at a top Chinese university has inflamed controversy over a gang-rape case by calling the act less harmful if the victim was a bar hostess.

Charges last week against Li Tianyi -- the 17-year-old son of an army general -- tapped into growing popular resentment at perceived privilege for elite families.

Li's family were reported as saying the alleged victim may have worked at the bar which the teenager and his friends were visiting -- prompting Yi Yanyou, a law professor at the prestigious Tsinghua University in Beijing, to step into the debate.

"Stressing the woman was a bar hostess is not to say that raping bar hostesses is okay, but that the likelihood that a bar hostess is willing to engage in sex is greater," he said on the popular Chinese microblog Sina Weibo.

"Even if it was rape, the harm of raping a bar hostess is less than raping a woman from a good family."

The post was not visible on his account on Wednesday, but media outlets shared images of it and many Weibo users vented their fury.

"How can an animal like this sneak into Tsinghua? What is going on with this country?" said one, calling Yi's comment "ignorant".

Social critic and author Li Chengpeng likened Yi's comment to saying it was less harmful for officials to beat street vendors than shop owners.

"A lot of people in China have this shameful logic," he said on Weibo.

Yi posted a brief apology on Wednesday evening, saying his comment was "not really appropriate" and had had a "negative impact".

A lawyer for the victim said in a statement she rejected the Li family claims about her and that no woman should face sexual assault, the Beijing Times reported.

"Just because some girls have had a drink with others, we cannot look at them with prejudice or carelessly infringe on their... right not to be sexually violated without any guilt or shame or legal responsibility," the statement said.

Bar hostesses in China are typically employed to drink with customers and the job has a reputation of potentially involving sex.

Li's father, Li Shuangjiang, holds the rank of general as dean of the music department for the army's academy of arts.

The teenager previously came under public scrutiny in 2011 after he and a companion, both driving expensive cars, attacked a couple for blocking their path.

He was sent to a correctional facility for one year and the general apologised for his son's actions.

Public resentment has mounted towards the children of high-ranking officials and rich families seen as living extravagantly or above the law thanks to their connections.

In a prominent scandal the son of a police chief in 2010 tried to assert his father's status to avoid responsibility after he ran over a student.

"Sue me if you dare. My father is Li Gang!" he cried, in what became a catchphrase referring to privileged children. He was later sentenced to six years in prison.