Somali forces have been struggling to contain the violence
A prominent Somali aid worker has been shot dead in the capital, Mogadishu, just days after a ceasefire agreement was signed.
The head of the local Woman and Child Care aid agency, Mohamed Mahdi, was killed by unidentified gunmen.
They opened fire on his car, as he was travelling through Mogadishu.
In a separate incident, five people were shot dead when gunmen carried out a hit-and-run attack on a police station in the city.
On Tuesday, Somali Islamist leader Sheikh Hassan Dahir Aweys rejected the UN-brokered, three-month ceasefire deal signed by Somalia's government and an opposition bloc in neighbouring Djibouti.
He promised to continue fighting until all foreign troops had left the country.
Premature peace deal
The peace deal was signed by another top Islamist leader, Sheikh Sharif Sheikh Ahmed, and Prime Minister Nur Adde.
Aimed at ending years of conflict, the deal provides for Ethiopian troops to leave Somalia within 120 days.
But the deal did not include many of the armed Somali groups fighting the transitional government and its Ethiopian backers.
Correspondents say they were not surprised by these latest killings.
At least 28 people died in clashes between Islamist insurgents and Ethiopian troops backing the Somali government over the weekend.
On Saturday, BBC Somali service reporter Nasteh Dahir was killed by suspected Islamist militants in the southern port of Kismayo.
Somalia has experienced almost constant civil conflict since the collapse of Mohamed Siad Barre's regime in January 1991.