The Chinese authorities must immediately release three citizen journalists detained since the weekend for highlighting a security crackdown in Beijing for the annual parliamentary session currently under way, said Amnesty International.

Liu Xuehong, Xing Jian and Wang Jing, - who all write for the Chinese website 64 Tianwang - were taken away by police in separate raids in Beijing over the weekend.

“Journalism is not a crime and these three activists should be released immediately,” said William Nee, China Researcher at Amnesty International.

“Their detention shows the disturbing lengths the authorities are willing to go to control the message during the National People’s Congress.”

The three citizen journalists have been criminally detained on suspicion of "picking quarrels and provoking troubles”. All had been reporting on the plight of petitioners near Tiananmen Square.

Scores of petitioners are being prevented from protesting as part of a security crackdown during the National People’s Congress China’s annual parliamentary session which began last Wednesday and runs for 10 days.

Security in the capital has been stepped up for the annual session, which usually draws thousands of petitioners from across the country to seek justice from the central authorities on a wide range of issues.

A woman attempted to set herself on fire in Tiananmen Square on the opening day, but was swiftly taken away by security officials. 64 Tianwang had reported on the incident.

The website – which is run by hundreds of volunteers - covers human rights news for a mainland Chinese audience.

The three citizen journalists are being held in detention centres in separate locations. Wang Jing was sent to a detention centre in her home town of Jilin in north-east China, while Liu Xuehong is being held in Beijing.

It is not known where Xing Jian, who at 17 years old is the youngest volunteer for 64 Tianwang, is being held.

On 8 March, six police officers also raided Liu Xuehong’s home in the capital and seized three computers, two cameras and one computer hard disk, according to her husband.