Witnesses in the Somali capital say at least 59 people have been killed in several days of heavy fighting between mostly Islamist insurgents and Ethiopian troops.

The dead include at least eight civilians killed Friday when Ethiopian forces fired shells into Mogadishu's Bakara market area, the scene of many clashes in recent months.

Human Rights Watch says both Ethiopian troops and insurgents have violated the laws of war in killing and wounding dozens of civilians. It also says tens of thousands of civilians are trapped in the city, with many of the wounded unable to access medical care.

U.N. Secretary-General Ban Ki-Moon says sending U.N. peacekeepers to Somalia is not a "realistic or viable option" under current conditions.

Ethiopia sent troops into Somalia in 2006 to help the interim government battle Islamist insurgents.

Ethiopia deployed as many as two-thousand additional troops to Mogadishu last week. The fighting has prompted hundreds of thousands of residents to flee the city for safer areas.

The United Nations refugee agency said earlier this week that many of those displaced Somalis are living in extremely harsh conditions, with little shelter and not enough water.

Some information for this report provided by AP and AFP.