by scenes of far-right youths hurling bricks at police and smashing cars as they piggybacked on street marches led by conservatives and Catholics against a reform to legalise same-sex marriage.

The sudden visibility of far-right groups is shaking up the already fragmented right-wing opposition, as National Front leader Marine Le Pen seeks to distance herself from them and the UMP conservative party squabbles over whether to embrace or oppose the anti-gay marriage movement.

Hundreds of people gathered on Thursday evening near the site of Wednesday's attack in central Paris, chanting left-wing slogans and paying tribute to Clement Meric, a political science student. Other vigils took place at Meric's university, Sciences Po, in the Latin Quarter of Paris and in other French cities.

Far-left youths in Toulouse plan to hold a daytime'Deadly fire' at Iran military explosives facility Published duration 6 October 2014

image copyright AFP/DigitalGlobe image caption One report says an explosion near the Parchin complex south of Tehran could be heard for miles

A fire and explosion at a military explosives facility near the Iranian capital Tehran has left at least two people dead, reports say.

The semi-official Iranian Students News Agency (Isna) said the fire was in an "explosive materials production unit".

A pro-opposition website reported a huge blast near the Parchin military site, south-east of the capital, but this was not confirmed.

Parchin has been linked to Iran's controversial nuclear programme.

The International Atomic Energy Agency (IAEA) has not been given access to the complex since 2005.

Analysts say the IAEA suspects Iran of experimenting with explosives capable of triggering a nuclear