Bloggers in China are using backward-written text as a means of evading censors while reporting on a riot that took place last weekend.

The troubles in Weng-an County in Guizhou province began following the death of 15-year-old Li Shufen on 22 June. The girl's death was labelled as suicide by authorities, but residents claim she was raped and murdered by people with connections to local officials.

Protests last weekend spiralled into riots involving 30,000 people and the burning of government buildings, but bloggers attempting to write about events online have been thwarted by the so-called Great Firewall of China – a complicated censorship system that automatically filters forbidden words and terms.

To counter this problem, users have begun to use programs that rearrange text to appear in reverse, reading right to left and down to up, rendering their reports invisible to the system. Other bloggers have used tools such as Twitter to send small bursts of information, at speeds that outstrip the censors.

China takes dissident action very seriously, and has clamped down on what it deems to be objectionable content in the run up to the Beijing Olympics next month.

Last week a court in Nanjing gave a four-year prison sentence to a blogger named Sun Lin, who had contributed to overseas site Boxun.com.