SANA, Yemen — Military and intelligence officials in Yemen said Wednesday they uncovered an Al Qaeda plot to fire missiles at foreign embassies in the capital and to attack naval forces guarding international shipping in the Red Sea.
Details of the plot, which was reminiscent of the suicide attack on the USS Cole in 2000 that killed 17 American sailors, emerged as Yemen remains in a heightened state of alert that has seen the US and British embassies evacuated and a new suspected US drone strike that killed seven alleged militants from the terrorist group.
The discovery of the Al Qaeda plot prompted the Defense Ministry to step up security around the strategic Bab el-Mandeb waterway, which connects the Red Sea with the Gulf of Aden. Officials banned speedboats or fishing vessels from the area, and military forces have been ordered to shoot to kill anybody who arouses suspicion or refuses to identify themselves.
General Mohammed Nasser Ahmed, the defense minister, visited the area Sunday and urged the forces, known as Battalion 117, to stay on high alert for possible suicide attacks, according to officials who spoke on condition of anonymity because they were not authorized to talk to the media.
An estimated 3.5 million barrels of oil passed daily in 2010 through the Bab el-Mandeb strait, increasing the importance of impoverished Yemen, which has only a relatively small production of oil and natural gas. Revenue from oil and gas production is declining, worsening its ability to provide social services.
The militants from the terrorist group’s Yemeni branch — known as Al Qaeda in the Arabian Peninsula — also were said to be plotting to use long-range missiles to target embassies and diplomats’ residences, or try to take foreigners as hostages, the officials said.
Ahmed urged the forces to stay ‘‘on alert against any sabotage operations aiming at destabilizing the country,’’ according to the officials.
Drastic security measures have been instituted across Sana, with multiple checkpoints set up, and tanks and other military vehicles guarding vital institutions.
In Sana, an Associated Press reporter said a drone buzzed over the capital for hours during the day.
Residents speak of their fears about possible terrorist attacks, although life is going on as normal, with shoppers buying new clothes and food for the four-day Muslim holiday of Eid al-Fitr.
A Yemeni government spokesman said earlier Wednesday that it had foiled a separate plot to target the southern cities of Mukalla and Bawzeer, then send militants disguised as Yemeni troops to attack two nearby strategic oil ports on the Arabian Peninsula, government spokesman Rageh Badi said.
Badi said other Al Qaeda militants would also try to sabotage oil pipelines to ‘‘create panic among Yemeni army and Yemeni security services.’’ Pipelines in the lawless south have been repeatedly attacked by Al Qaeda militants and armed tribesmen who maintain ties with the terrorist group.
Details of the plot were first reported by the BBC.
The Mideast official said the recent rise in drone strikes — five in 10 days — had been carefully coordinated with US officials together with Yemeni action on the ground in response to the threat from the Al Qaeda branch, which is considered the most active of the terrorist network.