SANAA, Yemen - Military and medical officials say clashes have killed a total of 19 people, including three children, in two Yemeni provinces.

Related readings: US pushes for immediate transition in Yemen  Saleh's return to Yemen challenged

They said dozens of unidentified gunmen attacked an army position in southern Abyan province late Monday night. The ensuing gunfight left nine soldiers and six of the attackers dead.

In Taiz, Yemen's second largest city, clashes erupted Tuesday between gunmen and army troops near the presidential palace. It was not immediately known whether there were casualties, but a shell fired by a tank near the palace landed at a nearby residential area, killing four people, including three children.

The officials spoke on condition of anonymity because they were not authorized to speak to the media.