Phnom Penh Municipal Court yesterday sentenced Mr Sam Rainsy and two other accomplices to one year and eight months imprisonment for instigating incitement and insult.
Judge Pich Vicheathor identified the two other as Ho Vann, an ex-CNRP lawmaker, and Kak Komphear, a former party member.
On the same day, Judge Vicheathor a also sentenced Kong Mas and Voeun Kemlun to one year and six months imprisonment, charged with incitement and insulting Prime Minister Hun Sen.
Only Mr Mas, a former CNRP activist from Svay Rieng province was present at the hearing yesterday.
Mr Mas fled to Thailand after the CNRP was dissolved on November 16, 2017.
He had requested refugee status from the UN High Commissioner for Refugees (UNHCR) in Thailand but was rejected. He was arrested on January.
The court yesterday also issued arrest warrants for Mr Rainsy, Ho Vann, Kak Komphear, and Kemloun who have fled..
The court spokesman Kuch Kimlong declined to give comment on further legal action.