Iran incensed by death of nuclear expert

TEHRAN, Iran -- Thousands of mourners chanted "Death to Israel" and "Death to America" Friday during the funeral of a slain nuclear expert whom Iranian officials accuse the two nations of killing in a bomb blast this week as part of a secret operation to stop Iran's nuclear program.

The assassination of Mostafa Ahmadi Roshan has raised calls in Iran for retaliation against the United States and Israel, and an independent news website yesterday said Iran is preparing a covert counteroffensive against the West.

Roshan, a chemistry expert and a director of the Natanz uranium enrichment facility in central Iran, was killed when two assailants on a motorcycle attached a magnetic bomb to his car Wednesday in Tehran.

Iran's Supreme Leader Ayatollah Ali Khamenei, who has the final say on all state matters, called Roshan's killing a "cowardly assassination" and accused the United States and Israel of being behind the attack. He vowed Thursday that the perpetrators and those who ordered the attack would be punished.

During a visit Friday to Lebanon, UN Secretary Ban Ki-Moon issued a vague condemnation of the killing, saying attacks on "any people, whether scientist or civilian," are not acceptable, according to UN spokesman Eduardo del Buey.

U.S. Secretary of State Hillary Rodham Clinton has denied any American role in the slaying, and the U.S administration condemned the attack. Israeli officials, in contrast, have hinted at covert campaigns against Iran without admitting involvement.