SANAA, Yemen — Government troops trying to recapture areas held by Islamic militants have killed 12 suspected al-Qaida members in the troubled southern province of Abyan, the Defense Ministry said Thursday.

The fighting comes amid fears of a breakdown of authority in the country as the regime is locked in an uneasy standoff with rebellious tribesmen in the capital, Sanaa, following the departure of President Ali Abdullah Saleh.

The Yemeni leader, who has clung to power in the face of months of massive street protests, is in Saudi Arabia to treat wounds he suffered in a rocket attack against his compound in Sanaa.

The United States fears that this power vacuum will give freer rein to al-Qaida's branch in Yemen — one of the terror network's most active franchises, behind two attempted terror attacks on U.S. targets.

The militants were killed in gunbattles as government troops pressed toward the provincial capital of Zinjibar, which was seized by Islamic militants last week. The Defense Ministry said the 12 were killed in the Doves and Kod areas but gave no more details.

Provincial military officials, speaking on condition of anonymity because they weren't authorized to release the information, said three soldiers also were wounded.

On Tuesday, the Defense ministry said its troops killed at least 30 militants just outside Zinjibar.

The Yemeni government consistently claims that the militants in Abyan are connected to al-Qaida. But their true identity remains unclear because Yemen has numerous armed Islamic militants and not all are affiliated with the terror network.

The Obama administration has intensified the covert U.S. war in Yemen, hitting militant suspects with armed drones and fighter jets, The New York Times reported late Wednesday.

The report said Yemeni troops that had been battling militants linked to al-Qaida in the south of the impoverished country have been pulled back to the capital to support Saleh's regime.

American officials hope the strikes will help prevent militants from consolidating power.

A drone strike by U.S. special operations forces on May 5 targeted U.S.-born al-Qaida cleric Anwar al-Awlaki, but a malfunction caused rockets to miss him by a matter of minutes, two U.S. officials told The Associated Press. The officials spoke on condition of anonymity to discuss intelligence matters.

The recent operations come after a nearly yearlong pause in American airstrikes, which were halted amid concerns that poor intelligence had led to bungled missions and civilian deaths that were undercutting the goals of the secret campaign.

Saleh authorized secret American missions in Yemen in 2009 but placed limits on their scope and has said publicly that all military operations have been conducted by his own troops.

The military officials said drones believed to belong to the United States have over the past week intensified their sorties over Abyan and the nearby province of Shabwa. Both are suspected to host militants from al-Qaida.