The trial of three members of the punk band Pussy Riot, who performed a song in a cathedral criticizing President Vladimir Putin, began in Moscow.

There was heavy security outside the court where supporters of the band held a demonstration. They shouted: "Freedom for Pussy Riot!".

The trio, who have been in custody since March, face seven years in prison if convicted on charges of hooliganism.

Nadeshda Tolokonnikova, Maria Alyokhina and Yekaterina Samutsevich, aged between 22 and 29, were arrested after the band in February occupied one of the pulpits at the Christ the Saviour Cathedral, Moscow's main Orthodox church, and sang: "Holy Mother, free Russia from Putin."

The court rejected an application by the defence to have the case referred back to investigators, alleging they had mishandled the investigation.

Lawyers also argued that they were given too little time to prepare for the case. They also objected to the decision to extend the women's custody till January.

Human rights activists have criticized the trial as being politically motivated.