Sana'a: A Yemeni press union has appealed to authorities to free an outspoken opposition editor sentenced to six years in jail for collaborating with a northern rebel group.

Union official Sami Ghalib says he handed over the petition to state prosecutor yesterday asking for the release of Abdul Karim Al Khawinay, editor of Al Shura weekly.

The editor, who was convicted and sentenced on Monday, has been known for harsh criticism of Yemen's president, articles on corruption and extensive coverage of a northern rebellion against troops.

Yemen has struggled with the rebellion by Al Zaydi sect since 2004, and thousands have been killed in clashes.