Iran protests: Khamenei blames Iran's ‘enemies’, hundreds held

Iran's supreme leader blamed the country's "enemies" on Tuesday for days of unrest that have seen 21 killed and hundreds arrested in the biggest test for the Islamic regime in years.

"The enemies have united and are using all their means, money, weapons, policies and security services to create problems for the Islamic regime," Ayatollah Ali Khamenei said in a speech carried on state television.

Iranian officials have said online accounts in the United States, Britain and Saudi Arabia are fomenting protests. A fifth night of unrest saw six protesters killed during an attack on a police station in Qahderijan in the central province of Isfahan, state TV said on Tuesday, reports AFP. At least three other towns near the cultural hub of Isfahan also saw violence overnight, causing the deaths of a young member of the Revolutionary Guards, a policeman and a bystander. The estimated death toll is now 21 since protests began in second city Mashhad and quickly spread to become the biggest challenge to the Islamic regime since mass demonstrations in 2009. "The enemy is always looking for an opportunity and any crevice to infiltrate and strike the Iranian nation," Khamenei said.The unrest appears leaderless and focused on provincial towns and cities, with only small and sporadic protests in Tehran last evening where a heavy police presence was reported.

As violence has spread, authorities have stepped up arrests, with at least 450 people detained in the capital since Saturday and 100 more around Isfahan on Monday, officials told local media.