A Chinese journalist jailed in part due to email evidence provided by a Yahoo subsidiary plans to file a lawsuit in the US against the internet company within the next few months.

"We're also trying to line up other victims for a class-action. We've been in touch with a few others, but we haven't signed anyone up yet. It's a very sensitive issue because there could be reprisals against their families," said Albert Ho, a legislator in Hong Kong and lawyer in the case.

A Yahoo spokeswoman in Hong Kong could not be reached for comment.

A US civil suit against Yahoo on behalf of Shi Tao, a Chinese journalist convicted of "divulging state secrets" by Beijing in part due to an email Yahoo provided to Chinese authorities, is likely to be filed in either New York or California, Ho said. Tao's email, sent from a Yahoo account in April 2004 to a pro-China democracy website in New York, contained a Beijing order for officials to be on guard for unrest and dissident activity ahead of the 15th anniversary of the Tiananmen Square massacre.

Tao was sentenced to 10 years in prison.

The new lawsuit would come just months after Ho filed a complaint to Hong Kong authorities against Yahoo Holdings (Hong Kong) on behalf of Tao. It also comes at a time when international pressure is increasing on internet companies to handle the private data of their users more carefully, particularly with respect to human rights.

Amnesty International and Reporters Without Borders have both criticised Yahoo over the Tao incident, and a group of US lawmakers blasted a group of internet companies earlier this year, including Yahoo, Google, Microsoft and Cisco for failing to uphold free expression in China.

"Internet companies should not disclose personal information that could violate the basic human rights of their users," Ho said.