Troublemakers in Iranian elections will be 'slapped', warns Khamenei

Ayatollah Ali Khamenei spoke during a graduation ceremony in Tehran for cadets in Iran's Revolutionary Guard - a hard-line paramilitary force. He warned that enemies of Iran seek "to create tension and sedition to disrupt order and security."

"Those who ignore the country's security will definitely be slapped in the face," Khamenei said, according to the state-run IRNA news agency.

Khamenei's comments came as the country's intelligence minister said his agents already disrupted one plot to cause unrest.

In an interview aired on Tuesday night, Intelligence Minister Mahmoud Alavi said his agents broke up a plot that would involve gangs of allegedly paid youths fighting each other.

Alavi also said the ministry detained suspected members of an Iranian opposition exile group, although no further information was provided.

Candidates must manage their campaigns "in a way that protects national solidarity and integrity while not damaging ethics and values of the society," Alavi said.

So far there has been no sign of major problems ahead of the May 19 election – although vandals have repeatedly broken windows at President Hassan Rouhani's campaign office.

In 2009, Iran witnessed months of unrest and dozens of deaths after the disputed re-election of former hard-line president, Mahmoud Ahmadinejad.

Authorities blocked Ahmadinejad from running in next week's election.