This document contains restrictions.VIET NAM, Hanoi : Reporters Nguyen Van Hai (2nd L, 2nd row, standing) from Tuoi Tre newspaper and Nguyen Viet Chien (C, 2nd row) from Thanh Nien newspaper are seen along with police officers colonel Dinh Van Huynh (C, standing, 1st row).

Convicted ... the three journalists stand on trial. Photo: AFP

THE United States and human rights groups have criticised the jailing of three prominent Vietnamese bloggers for between four and 12 years in a crackdown on online dissent in the communist state.

Charges laid against the three founding members of Vietnam's ''Free Journalists Club'' were seen as an attempt to stifle challenges to the government on the internet, which has emerged as a major avenue for dissent in the country.

US State Department spokeswoman Victoria Nuland said: ''We are deeply troubled by the convictions of three Vietnamese bloggers who appear to have done nothing more than exercise their right to freedom of expression.''

Human Rights Watch spokesman Phil Robertson said the harsh sentences were ''absolutely outrageous''.

''By its actions, the Vietnam government is showing contempt for international human rights and daring the international community to do something abut it,'' he said.

Nguyen Van Hai, who has written under the pen name Dieu Cay, or Tobacco Pipe, was sentenced to 12 years' jail after a six-hour trial in a Ho Chi Minh City court on Monday.

Ta Phong Tan, a former policewoman, was led from the court screaming after receiving 10 years' jail. Earlier, her mother had self-immolated to protest against her detention.

Phan Thanh Hai, the only one of the trio who had pleaded guilty, received four years.

US President Barack Obama mentioned Nguyen Van Hai's case in a May speech that called for greater media freedom around the world. The blogger had criticised the government's handling of its dispute with China over the South China Sea.

Private media are banned in Vietnam and all newspapers and television channels are state-run.

With AGENCIES