Nairobi - A Kenyan newspaper journalist has been jailed for 18 months without the option of a fine for publishing an "alarming report", his newspaper said on Tuesday.

A court in the western town of Kitale last week found Johann Wandetto, a reporter on the People daily, guilty on the charge of "causing the publication of an alarming report", the People's news editor Mukalo wa Kwayera said.

The report carried by the newspaper in March last year claimed that bandits had ambushed and disarmed the guards of President Daniel arap Moi in the northwestern Pokot district, the court heard.

The press freedom group Reporters Without Borders (RSF) said it had written to Kenya's Attorney General Amos Wako calling for Wandetto's release.

"RSF reminded him (Wako) that international human rights organisations believe that prison as punishment for press offences such as libel is out of proportion to the harm suffered by the victims," RSF said in a statment. - Sapa-AFP