PHNOM PENH, Dec. 5 (FN) -- The Phnom Penh Municipal Court of Cambodia on Monday sentenced commune chief of opposition Sam Rainsy Party Seang Chet to five years in prison for bribery.

Chet appeared in the courtroom to hear his verdict. During a trial session last month, he admitted to having handed about 500 U.S. dollars to the mother of Khom Chandaraty, the alleged mistress of Kem Sokha, deputy leader of the main oppositon Cambodia National Rescue Party (CNRP).

Sam Rainsy Party, which holds nine seats in the Senate, is one of two parties which merged into CNRP but remains active separately due to its seats in the Senate. The CNRP is the largest opposition party in the parliament against ruling Cambodian People's Party.

Seang Chet was arrested and charged in April after being accused of bribing Chandaraty to convince her to deny her alleged affair with Kem Sokha, deputy leader of CNRP.

The alleged sex scandal between Chandaraty and Kem Sokha came to light in February with leaked audio clips of their telephone conversation. In the clips, they discussed sex, pregnancy and payment for an apartment.

Kem Sokha, 63, was pardoned by King Norodom Sihamoni on Friday at the request of Prime Minister Samdech Techo Hun Sen after the country's Appeal Court convicted him of refusal to appear in court over a prostitution case.

Currently, four local human rights officers and an election official are still in a pre-trial detention on the same charges of bribing Chandaraty to deny her alleged affair with Kem Sokha.