Much of colonial-era Baidoa is in ruins left from the war that toppled Somalia's last functioning government in 1991.

A two-minute drive from the airport lies the bullet-scarred shell of Baidoa's colonial-era palace. The graffiti-covered walls, adorned with a black al-Shabab flag, testify to the extremists' recent presence, and their links to al-Qaida. 

Now, this once-splendid mansion is Ethiopia's command post. General Yohannes Woldegiorigis says the compound was captured without a shot.

"There was no resistance. They were displaced and ran away from the bases,” the general said.

A statement from al-Shabab said the departure from Baidoa was a “tactical retreat” and it promised to return.

As if to remind Baidoans of their power, the extremists left behind a few surprises. Army Captain Mahamoud Yssak displays crude bombs and remote detonators found by advancing troops.

"They use these things for mortars to shell. This is a shelling point. This is also a switch. So this thing is improvised explosive device," Mahamous said.

Ethiopia's last military push in Somalia ended badly in early 2009. Al-Shabab successfully portrayed the Ethiopians as Christian invaders out to destroy Somalia's Islamic culture. But now, Captain Mahamoud Yssak says after three years of harsh rule in which al-Shabab refused to allow food aid to reach Somali famine victims, Ethiopians are being welcomed back.

"Al-Shabab, they did many wrong things to people. They [didn't] allow NGOs [aid groups] to come here. There is drought, there are no [aid groups] here. So this is why people hate al-Shabab," he said

At a briefing for reporters, clan elders likened the damage inflicted by al-Shabab's rule to an earthquake. Elder Maalim Ali Badheere said no aid organizations had arrived since al-Shabab's departure, and he appealed to the international community for urgent disaster relief.

“A lot of people are dying. They are hungry and thirsty and in desperate need of international assistance," he said.

Regional governor Abdifatah Mohammed Ibrahim says long-term military aid will also be needed to prevent al-Qaida-linked forces from making a comeback. 

As the governor showed reporters truck-mounted machine guns captured from fleeing Shabab fighters, he said the extremist threat could only be eliminated when their fighting force is destroyed.

"You know the character of al-Shabab. They like to fight, hit-and-run. So I think they will be back. They are [just] hiding here, under trees," the governor said.

Ethiopian officials remember the unpleasant end to their last stay in Somalia. They have promised to leave Baidoa as soon as conditions are stable. But the extremists have not been defeated, they have only melted into the countryside. Stability appears to be a long way off.