University student Kong Raiya was released from Prey Sar prison yesterday after serving an 18-month sentence for a social media post calling on Cambodians to mount a colour revolution – a term that, despite its non-violent associations, has become something of a red cape to the ruling party.

Raiya was arrested in August 2015 and convicted of “incitement” in March the following year after he used a Facebook post to call on Cambodians to “launch a colour revolution” in order to replace the “cheap regime” running the country, an apparent reference to the ruling Cambodian People’s Party.

“Colour revolution” is a term commonly used to refer to non-violent uprisings that have toppled governments in the Middle East and Eastern Europe.

“I am not afraid and I already know what prison is,” Raiya said outside of Prey Sar yesterday. “I will continue to express these opinions even more actively than before.”

Raiya said he would return to his studies with the aim of working in the education sector, but lamented the “hellish” conditions at Prey Sar.

“There are 30 prisoners per cell and they smoke hundreds of cigarettes,” he said.

Licadho’s Am Sam Ath said that while he was pleased to see Raiya leave prison, he shouldn’t have been there in the first place. “He was charged with incitement; that affects his right to freedom of expression, and this will be like a threat to other youth as well,” he said.

Speaking by phone later, Raiya said that he “was also not allowed to meet other political prisoners, and had to argue a lot to meet Adhoc staffers at jail”.

Yesterday marked 300 days since the five current and former rights workers – Adhoc’s Lim Mony, Nay Vanda, Ny Sokha and Yi Soksan, and the National Election Committee’s Ny Chakrya – were jailed for a case related to a sex scandal surrounding CNRP acting president Kem Sokha.

The five were arrested on “bribery” charges after Sokha’s alleged mistress, Khom Chandaraty, to whom Adhoc had been providing assistance, accused them of asking her to lie about her alleged affair with the opposition leader.

Since the Adhoc arrests last April, Sokha and a Sam Rainsy Party commune chief, Seang Chet, have been convicted and pardoned in relation to the scandal, but a hoped-for political deal in December that would have seen the five released yielded no results.

All seven of the cases are widely believed to be politically motivated.