Human rights group Amnesty International said on Saturday that more than 50 human rights lawyers and activists in China had been "detained, disappeared or summoned by police" over the past 48 hours, with a number of them having failed to make contact with relatives since coming into the hands of the authorities.

"We've seen detentions or people being disappeared or having their freedom of [movement] curtailed in many cities all around China," said William Nee, Amnesty's Hong Kong-based China researcher.

"Clearly it is a nationwide crackdown. The most recent estimate we have is 48 people," Nee added.

Prominent law firm targeted

Lawyers at the Beijing Fengrui law firm, known for its work on human rights cases, said several staff there had been detained by police, with some "forcibly taken away," according to a posting on Twitter.

The brother and a family friend of Zhang Miao, a Chinese news assistant employed by the German weekly "Die Zeit" to report on pro-democracy protests in Hong Kong, said one of those detained at the firm was her lawyer, Zhou Shifeng. Zhou was reportedly taken from his Beijing hotel by state security on the day of her release.

Zhang was released on Thursday after having been in detention since October.

Amnesty said at least seven people working at Fengrui were in some form of detention and that relatives had had no sign of them for days.

Vague definition

Nee said the arrests could be connected with security legislation approved by China this month, which gives the state powers to take "all necessary measures" to protect its sovereignty. The law also calls for "bad cultural influences," "malignant groups" and "criminal activities under the guise of religion" to be combated.

The law has come under criticism from the United Nations for being too vague in its definition of what constitutes a security threat.

"[The law] leaves the door wide open to further restrictions of the rights and freedoms of Chinese citizens, and to even tighter control of civil society by the Chinese authorities than there is already," the UN's high commissioner for human rights, Zeid Ra'ad Al Husseid, said in Geneva on Wednesday.

tj/sms (dpa, AFP, AP)