Police in Hanoi have fined five people up to VND20 million (US$900) each for running Facebook pages that tell people how to avoid police officers.
The men, all in their 20s, were punished for revealing locations of the police's random checkpoints.
They said they did not run the pages for personal gains and that they only helped others avoid the traffic police.
Two young men in the northern city of Hai Phong were sentenced to six months in jail last December for running similar Facebook pages. They also posted defamatory comments against the police and tried to sell their pages.