China is in the middle of yet another crackdown on what it terms "online rumours", as the government tries to rein in social media, increasingly used by Chinese people to discuss politics, despite stringent censorship.
According to a judicial interpretation issued by China's top court and prosecutor, people will be charged with defamation if online rumours they create are visited by 5,000 internet users or reposted more than 500 times.
That could lead to three years in jail, state media reported. That is the standard sentence for defamation.
"People have been hurt and reaction in society has been strong, demanding with one voice serious punishment by the law for criminal activities like using the internet to spread rumours and defame people," said court spokesman Sun Jungong.
The interpretation also set out what is considered a "serious case" of spreading false information or rumours online, including those which cause mental anguish to the subjects of rumours.
Other serious cases involve the spreading of false information that causes protests, ethnic or religious unrest or has a "bad international effect".
Users of China's popular Twitter-like Sina Weibo microblogging site expressed anger about the new rules.
"It's far too easy for something to be reposted 500 times or get 5,000 views. Who is going to dare say anything now?" wrote one Weibo user.
"This interpretation is against the constitution and is robbing people of their freedom of speech," wrote another.
State media have reported dozens of detentions in recent weeks as the government pushes a crackdown on the spreading of rumours.