(Adds loss of key town)
MOGADISHU, March 26 (Reuters) - At least two people were killed and 8 others wounded after mortar rounds fired by Somali rebel group al Shabaab towards the presidential palace landed on a nearby camp for the internally displaced, witnesses and officials said on Monday.
Under pressure from African Union and Somali government troops, the al Qaeda-linked militants withdrew from Mogadishu in August prompting a return to relative calm in the capital, although they still manage to launch sporadic attacks.
Paddy Ankunda, spokesman for the African Union force known as AMISOM, said some mortars hit a camp for Somalis displaced by war and famine about 300 metres from the presidential palace.
Ismail Nur, a resident of the camp, said one mortar killed two members of a single family.
"A mortar landed on our camp - a father and his son died. Eight others including three women were injured," Nur, who is a nephew to the dead father, told Reuters.
Al Shabaab said they fired mortars at the heavily protected presidential compound, their third attempt to strike at the heart of the government in a fortnight.
The group also lost control of a strategic town in central Somalia to Ahlu Sunna, a pro-government militia and Ethiopian troops.
They abandoned El Bur, about 90 km to the south east of Galgadud region capital, Dusamareb. The town was stronghold of the group in central Somalia for years.
"We are now in El Bur, the biggest al Shabaab stronghold that gave us a headache for years. (There was) no resistance," Abdiweli Syad, Ahlu Sunna commander for Galgadud region told Reuters on Monday.
Al Shabaab confirmed they had lost the town, saying it was a tactical retreat and they would engage the militia and the Ethiopians in guerrilla warfare.
"Ethiopian tanks and the so-called Ahlu Sunna are now in the town, but they will never control the town peacefully," Sheikh Abdiasis Abu Musab, the spokesman for al Shabaab's military operation told Reuters. (Reporting by Abdi Sheikh and Feisal Omar; Editing by Duncan Miriri and Toby Chopra)