A Chinese court has sentenced a 71-year-old journalist to seven years in jail for leaking state secrets.

The case is seen by rights groups as part of a crackdown on government critics.

Gao Yu, named one of the International Press Institute's 50 "world press heroes" in 2000, "illegally provided state secrets to foreigners", Beijing's No. 3 Intermediate People's court said on a verified social media account.

One of Gao's lawyers, who argued in court that a confession from her had been extracted after threats were made against her son, says they're very disappointed with the verdict.

A researcher with Britain-based Amnesty International says Gao is the victim of vaguely worded and arbitrary state-secret laws that are used against activists.