(AP) SANAA, Yemen - Government troops battling al Qaeda fighters in southern Yemen have made inroads into the militants' strongholds, but the offensive on a strategic city has slowed because of concerns the extremists could launch a surprise counterattack, military officials said Thursday.
Backed by heavy artillery and warplanes, Yemeni troops have advanced into Zinjibar, the capital of Abyan province, which fell under the control of al Qaeda-linked fighters last year as the country was engulfed by political turmoil that led to the ouster of longtime leader Ali Abdullah Saleh.
If the military were to capture Zinjibar, it would deal a heavy blow to al Qaeda by depriving it of a key base and scattering its fighters to smaller towns and mountain areas of the south.
Yemeni officials said the assault on Zinjibar, which is part of the government's broader offensive aimed at uprooting al Qaeda in the south, has slowed down in part because of poor intelligence in the city. They said army commanders were unsure whether most of the militants there have been killed, simply fled the battle or retreated for tactical reasons and were preparing a counteroffensive.
The U.S. is deeply concerned about al Qaeda's branch in Yemen, known as al Qaeda in the Arabian Peninsula, which was behind three failed bomb plots on U.S. soil. Washington has thrown its support behind Saleh's successor, Abed Rabbo Mansour Hadi, who has vowed to tackle the threat from al Qaeda in the country.
As part of the fight, Hadi is restructuring the military and removing Saleh's loyalists from key posts, though there are concerns that the former leader, who stepped down in February, is still obstructing reforms and trying to retain influence through his cronies.
On Wednesday, President Barack Obama signed an executive order allowing the Treasury Department to freeze the U.S.-based assets of individuals who the White House says "threaten the peace, security and stability" of Yemen. The order was meant as a deterrent against future action and does not immediately levy any penalties against specific people or organizations.
Yemeni officials point to an ongoing power struggle between Hadi and Saleh.
In one recent example, officials say Saleh's son Ahmed, who commands the elite Republican Guard, has sought to undermine a Hadi-appointed commander of one of the Guard's battalions. The officials say Ahmed has been stirring up dissent within the battalion, making it impossible for the Hadi appointee to assume control.
Three foreign diplomats told The Associated Press that they have met with Ahmed to try to convince him to allow the new commander to take his post.
One diplomat warned Ahmed this week that by blocking the commander's appointment, he is undermining the power-transition deal that his father signed and that assured him immunity from prosecution.
Washington is also directly aiding the Yemeni military in its latest offensive. U.S. troops are operating from a desert air base near the main battle zones to help coordinate assaults and airstrikes, according to Yemeni officials.
The officials said it was the most direct American involvement yet in the country's expanding campaign against AQAP.
Also Thursday, Yemeni military officials said a suspected U.S. drone-fired missile struck two vehicles in the city of Shibam in Hadramawt province. The officials said the strike destroyed one of the vehicles, killed its three occupants who were believed to be linked to al Qaeda, and wounded two in the second car.
Yemeni warplanes, meanwhile, struck a vehicle in the town of Shaqra, killing six suspected militants, officials said.
Also in the south, the bodies of 11 Yemeni army soldiers and civilian volunteers fighting alongside the military were found after al Qaeda retreated from an area near the city of Lawder, officials said. The victims were believed to have been killed execution-style, they said.
"Most of the areas surrounding Lawder are clear of al Qaeda now," one military official said.
All the officials spoke on condition of anonymity because they were not authorized to talk to the media.
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