"We entered the city centre (of Mukalla) and were met by no resistance from Al-Qaeda militants who withdrew west" towards the vast desert in Hadramawt and Shabwa provinces, said the officer, speaking to AFP by phone from the city which the jihadists seized last April.
The officer who requested anonymity told AFP that residents of Mukalla, home to an estimated 200,000 people, had appealed to the jihadists to spare the city the destruction of fighting and pull out.
Troops also recaptured Mina al-Dhaba oil terminal in Shehr, further east, the sources said, while a provincial official in Shabwa said jihadists had fled from the nearby city of Azzan.