Iranian authorities will this week crack down on any public protest against the year-long house arrest of opposition leaders Mirhossein Mousavi and Mehdi Karoubi, an official said yesterday.

A pair of gunmen firing from motorcycles killed an Iranian physicist involved in the country's disputed nuclear programme today in an attack similar to other recent assassinations of scientists which Tehran has blamed on the US and Israel.

HUNDREDS of young men and women chanted “Death to the dictator”, confronting police wielding batons and firing tear gas in the capital yesterday as opposition activists sought to revive street protests despite authorities’ vows to “smash” any new marches.