U.S. Secretary of State Condoleezza Rice has condemned the assassination of Sri Lanka's Foreign Minister Lakshman Kadirgamar, calling it "a senseless murder and vicious act of violence."

Ms. Rice urged Sri Lankans to remain calm and not to let the assassination lead to a resumption of civil war. She said her Sri Lankan colleague was a man of dignity, honor and integrity, who devoted his life to bringing peace to his country.

United Nations Secretary-General Kofi Annan expressed shock and sadness at what he called Mr. Kadirgamar's criminal and senseless murder.

Norweigan officials involved in mediating the Sri Lankan conflict described the foreign minister's death as a major setback for the fragile peace process.

Some information for this report provided by AP and AFP.