Who alerted them ?
ELBUR, Somalia - Islamist group Al-Shabaab retreated from their strongholds
within Central Somalia, reports have emerged, amid an ongoing crackdown against the terrorists, which is engineered by the Somali National Army [SNA], AU forces, and the US Africa Command team.Reports indicate that the Al-Shabaab militants withdrew from Elbur town within Galgadud in Galmadug state after it emerged that the SNA troops and a contingent of Ethiopian National Defense Forces [ENDF] were planning to unleash a major assault against the militants.
Heavily armored military vehicles mainly driven by Somali National Army and the Ethiopian non-AMISOM troops made into the town, forcing the militants to quickly disappear to neighboring villages and thickets, sources said, but it's not clear if they will retaliate against the government forces.
Source: Garowe