SANAA, Yemen (AP) - Yemeni officials say a large explosion has
killed three security personnel in the southern port city of Aden.

The blast was heard throughout the city, where a large
anti-government demonstration was taking place Friday.

A medic and a security official say the cause of the explosion
in the free trade area of the city is not yet known. They spoke on
condition of anonymity because they were not authorized to talk to
journalists.

Residents of Aden say the military recently removed checkpoints
at the city's entrances, raising fears that Islamic militants who
have seized nearby towns could attempt a takeover of the strategic
port city.

The U.S. fears months of political turmoil in Yemen will give
al-Qaida's franchise in the country more room to operate freely.

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