Al-Qaida-linked militants staged a dawn attack on an army post in south Yemen today, setting off clashes which left 23 dead on both sides, Yemeni army officials said.

Wounded Yemen President Ali Abdullah Saleh tonight called on armed forces around the country to move against the “armed gangs” who hit his palace with rockets.

Government forces and tribal fighters exchanged gun and artillery fire in Yemen’s capital Sanaa this morning in fresh fighting that killed at least 41 people.

Three Yemeni army commanders have defected to the opposition, calling for an end to President Ali Abdullah Saleh’s rule, as army tanks and armoured vehicles deployed in support of thousands protesting in the capital.