Yemeni government airstrikes that accidentally killed 40 people last week, including four army officers and a tribal sheik, brought an abrupt halt to the largest military effort yet to dislodge al-Qaida-linked militants from a key southern town, officials and tribal fighters said Tuesday.
The airstrikes, which took place late Friday just east of the town of Zinjibar near Yemen's south coast, outraged pro-government fighters, prompting them to withdraw from the military offensive against Islamist militants.
The collapse of the offensive on Zinjibar will likely raise concerns among American officials, who worry that Yemen's active al-Qaida branch and other militant groups are exploiting political upheaval in the impoverished country to step up operations against the West.
Security has crumbled across Yemen since the popular uprising seeking to oust President Ali Abdullah Saleh from power began in January. Armed tribesmen opposed to the government are battling security forces in some areas, while al-Qaida-linked militants have overrun several towns in the south, including Zinjibar, the capital of Abyan province.
After clashing with the militants for months, the military launched a fresh offensive last week with a joint force of army troops and pro-government tribesmen from the region to reclaim Zinjibar, security officials said.
Tribal loyalties are paramount in Yemen, and the approach seeks to leverage this in the fight against the militants. Tribes throughout restive Abyan province have increasingly turned against the militants, whom they consider outsiders trying to seize control of tribal territory.
Over the last month, tribal fighters have pushed militants from two other towns in the province, Lawdar and Wudia, security officials and tribal leaders said.
Last week, tribal fighters advanced with government troops on Zinjibar, the provincial capital, reaching the city's eastern outskirts and taking over a government communications building when they were hit with at least three airstrikes.
While officials confirmed the death count last week, the deaths of high-ranking leaders were not made public until Tuesday.
Ali Gaadani, a regional security chief in Abyan, said the dead included two colonels, a lieutenant colonel, a major and a powerful sheik from one of the tribes participating in the campaign, the Nahee.
The strikes brought the campaign to a halt, Gaadani said. The tribal fighters withdrew and returned to their villages to bury their dead, he said. Since then, the militants have solidified their control over the town.
Mohammed Gaadani, a fighter who survived the strikes, said they destroyed the fighters' morale and undermined their trust in the Yemeni government, especially since he said his forces had notified the government of their location.
"It was not just one strike or two, but three in a row!" Gaadani said. "This has made people very doubtful."
He said the tribes had not yet decided whether to resume the offensive, but that they first demand a government apology.
Military officials said last week that the strikes appeared to have been made in error. A Defense Ministry official said Tuesday that an investigation is under way.
Hubbard reported from Cairo.