Officials in Somalia's capital say at least 18 people were killed in an incident involving African Union peacekeepers Monday.
The AU force, known as AMISOM, and local officials both say a roadside bomb exploded and damaged an AU peacekepeeing vehicle in southern Mogadishu.
Officials including the deputy mayor, Abdifitah Ibrahim Shaweye, say AU troops then fired on civilians, killing at least 18 of them.
However, a spokesman for AMISOM, Major Bahuko Baridgye, denies the peacekeepers opened fire. There was no way to immediately reconcile the accounts.
Violence is still common in Mogadishu despite a recent peace deal between the government and moderate Islamists and the pullout of Ethiopian troops supporting the government.
Hardline Islamist groups such as al-Shabab rejected the deal and have vowed to target the AU peacekeepers, whose job is to protect key government installations.
On Friday, Somali lawmakers elected moderate Islamist leader Sheikh Sharif Sheikh Ahmed as the country's new president in hopes of stabilizing Somalia.
Thousands of died and hundreds of thousands more have been displaced during a two-year Islamist insurgency.
The country has not had a stable central government since 1991.
Some information for this report was provided by AFP and AP.