Two Mother Nature activists imprisoned since September for documenting suspected illegal sand-bearing vessels in Koh Kong were released this morning.

Activist Lim Kimsor confirmed that Hun Vannak, 35, and Dem Kundy, 21, were released from Koh Kong Provincial Prison after concluding their sentences. The two were found guilty late last month of “incitement to commit a felony” and making unauthorised recordings of a person “in a private place”, despite the recording taking place on the open ocean.

The pair was arrested in September while filming and taking photos of two boats off the coast of ruling party Senator Ly Yong Phat’s special economic zone in Kiri Sakor district. After more than four months in detention, they were found guilty of the charges during a one-day trial and were sentenced to a year in prison sentence, with seven months suspended.

In Kong Chit, a provincial coordinator for rights group Licadho, said the two had simply been working to protect and preserve the country's resources, and never should have been charged. Their sentences could deter other young people from being involved in activism, and the conviction will leave a "historical scar" on both men's records, he added.

Updates to follow.

Read more: How Mother Nature duo followed their principles into activism — and a trial