US spy agencies snooped on the emails of five high-profile Muslim Americans in an effort to identify security threats, documents leaked by fugitive ex-NSA contractor Edward Snowden show.

The targets include a lawyer, professor and a political operative, according to a report published in the Intercept.

The Intercept is an online news site overseen by Glenn Greenwald, who helped publish many of Mr Snowden's leaks.

The FBI and NSA said they only spied on Americans when they had probable cause.

"The National Security Agency and FBI have covertly monitored the emails of prominent Muslim-Americans... under secretive procedures intended to target terrorists and foreign spies," according to The Intercept report.

(BBC)