The officials say 20 militants and seven soldiers have been killed in fighting near Zinjibar, the capital of southern Abyan province, that continued from Friday until early Saturday. They say seven other militants have been killed in nearby Jaar.
The officials spoke on condition of anonymity in line with regulations.
Brig. Gen. Mohammed al-Somali, commander of the 25th Mechanized Brigade, says the army has advanced deep into Zinjibar. The town fell last year to al-Qaida, who took advantage of political turmoil to extend their control over much of the south.