By Aaron Maasho
ADDIS ABABA (Reuters) - A military offensive by Somali and African Union forces has pushed al Shabaab Islamists into two dwindling pockets of territory, in the north and south, the AU's special envoy said.
Al Shabaab, which controlled Mogadishu and southern Somalia until it was driven out of the capital in 2011 has steadily lost territory since. But it still launches guerrilla-style attacks, and was blamed for a car bomb that severely wounded a university lecturer on Wednesday.
An African Union force, known as AMISOM, and Somali soldiers have recaptured swathes of territory since launching an offensive last year which the AU envoy said had driven al Shabaab from "85 percent" of areas it had controlled.
"When they were hit by AMISOM, the tail went down to the Jubba valley and the head towards Puntland," Maman Sidikou told Reuters, referring to the regions to the south and north.
Sidikou said al Shabaab had its biggest concentration of forces in the fertile stretch of land straddling the Jubba river in the south.
He would not give details of further offensives but said: "Discussions are ongoing and plans are very much advanced."
Al Shabaab says the offensive has not diminished its ability to strike across the southern central region to cut off supply routes.
The semi-autonomous, northern region of Puntland has been relatively calm but in the past week Puntland troops have battled al Shabaab forces in the Galgala hills region.
Puntland authorities say they killed 20 rebels and lost five soldiers and now control the battleground. Al Shabaab said it had killed 23 troops and that fighting was ongoing.
As well as guerrilla attacks in Somalia, al Shabaab has hit neighboring Kenya, which has sent forces to AMISOM.
Other AMISOM contributors are Uganda, Burundi, Djibouti and Ethiopia. Sierra Leone is a contributor but is pulling out, with other remaining states filling the gap, Sidikou said.
(Editing by Edmund Blair and Robin Pomeroy)