Amnesty International has condemned what it says is reckless and excessive use of force by Kenyan police against opposition protesters. Police and witnesses say at least 12 people died Friday in another day of unrest in the East African nation.

Amnesty's Africa program director, Erwin van der Borght, says police fired live ammunition into crowds this week during three days of protests against President Mwai Kibaki's disputed re-election. Amnesty has called on the Kenyan government to intervene, and to stop the police from using excessive force.

The London-based rights group also is seeking an independent inquiry into this week's bloodshed. Including Friday's deaths in the port city of Mombasa, the Kibera slum in Nairobi and the southwestern town of Narok, at least 22 people have been killed since Wednesday. The overall death toll since late December is more than 600.

Police say some of those shot to death were criminals; they deny that they killed innocent civilians indiscriminately.

This week's nationwide protests were called to press the opposition's charge that Mr. Kibaki's re-election on December 27th was tainted by fraud. Because of the violence, however, the opposition says no further rallies are planned. Protesters say they will switch tactics and launch economic boycotts against at large companies such as Equity Bank and City Hoppa transport owned by Mr. Kibaki's supporters.

The United Nations says former Secretary-General Kofi Annan will travel to Nairobi on Tuesday to try to mediate the political crisis. Illness delayed Mr. Annan's scheduled arrival in Kenya earlier this week.

American and African diplomats have tried without success to work out an agreement between President Kibaki and opposition leader Raila Odinga to would end the violence.