PHNOM PENH (Reuters) - A Cambodian court on Friday sentenced two environment activists to a year in jail, with a suspension of seven months each, after they were convicted of filming suspected illegal sand export activity.

The court in southewestern Koh Kong province sentenced Dem Kundy, 21, and Hun Vannak, 35, members of the conservation group Mother Nature, their defense lawyer, Sam Chamroeun, said. Each was also fined $250.

“They are innocent all along,” he told Reuters of the two activists, whom rights group Amnesty International considers prisoners of conscience.

Dem Kundy and Hun Vannak were arrested on September 12 last year and convicted of violation of privacy and incitement to commit a felony when they filmed vessels suspected of illegally carrying sand for export.

Cambodia banned all sand exports last year, officially ending the sale of sand to the wealthy city state of Singapore which has for years used it to reclaim land along its coasts.

Skeptical about whether the ban was being properly enforced, Mother Nature and other groups pressed the government to stop the trade, saying the digging and dredging of sand has had a serious impact on coastal ecosystems and surrounding land.

The sentences came a day after their trial on Thursday.

But domestic rights group Licadho said there was insufficient evidence to convict.

“It’s shocking that the two Mother Nature youths were convicted by the Koh Kong court for only trying to protect and preserve natural resources for the current and future generations in Cambodia,” said Naly Pilorge, its director.

Cambodia expelled Spanish national and co-founder of Mother Nature, Alejandro Gonzalez-Davidson, in February 2015.