Following heavy air raids overnight in the north, coalition aircraft also hit the presidential palace in the southern city of Taez, the witnesses said.
Air strikes also hits the southern capital Aden, a military source said.
Thirty-six other people died in bombing around Aden and Taez.
The UN says hundreds of people have died and thousands of families fled their homes in the war which has also left six Saudi security personnel dead in border skirmishes.
UN chief Ban Ki-moon called for an immediate ceasefire and began the hunt for a new peace envoy to the country where Al-Qaeda is expanding its territory.
Yemen "is in flames", Ban told reporters in Washington on Thursday. "I am calling for an immediate ceasefire in Yemen by all parties."
Yesterday people of Yemen protest against Saudi Arabia airstrike.