WRAPUP 2-Yemen forces kill 12; insurgents wreck gas pipeline

(Adds U.S. comment, Awlaki tribal leader, attack in al-Mukalla)

* Twenty-three other militants killed in attack on al Qaeda official

* Militants respond by blowing up Yemen's gas pipeline

* Yemeni forces kill 8 demonstrators, 4 tribal fighters in Sanaa

* Total evacuating some foreign staff, sending teams to repair pipeline (Adds quotes, background, LNG details)

By Mohammed Sudam and Mohammed Mokhashef

SANAA/ADEN, Oct 15 (Reuters) - Security forces shot dead at least 12 people protesting against the rule of Yemeni President Ali Abdullah Saleh in the capital Sanaa on Saturday and al Qaeda insurgents blew up a pipeline, halting the nation's gas exports.

Yemeni officials said the attack on France's Total gas pipeline was in retaliation for the killing of the head of the media department of al Qaeda in the Arabian Peninsula in an air raid on militant outposts in Yemen.

In Sanaa, security forces shot dead at least 12 demonstrators as Yemenis waited for the U.N. Security Council to agree to a resolution expected to urge Saleh to hand over power under a Gulf Cooperation Council (GCC) peace plan.