THEIR faces are blacked out in their photographs on their official website.

They own a warehouse where CCTV cameras keep watch over who is coming and going for security purposes.

They have a hierarchy, refuse to speak with the media and are being watched closely by the police.

While this may sound like the characteristics of Sydney's next outlaw gang, it is actually a group of proud but hardcore football fans, known as the Red and Black Bloc (RBB).

While the vast majority of its members are well behaved, police are concerned about the potential for criminal behaviour. For now the behaviour has been limited to offensive language, setting off flares and the odd scuffle but, left unchecked, authorities fear this could escalate further. Already, extensive intelligence targeting is being used to find those with an interest in causing trouble.

What police are emphatic about avoiding is any rise in hooliganism or "firms", where football fans deliberately form groups aligned to their beloved clubs to prey on or fight willing members from opposing teams. These were the scenes that played out in Melbourne on December 28 when members of a Melbourne Victory support group allegedly attacked visiting fans supporting the Wanderers.

Earlier this year, a small group of skinheads were understood to have infiltrated the Northgate faction, but police say they have since disappeared and no longer attend matches. The RBB is steered by a group of about six individuals who regularly meet with police before matches.

Its members are devoted to the point of fanaticism. It takes on average three nights to cut up enough newspapers to make the confetti that is let off in the stands during games.

Their fundraising and merchandise sales have also been used to support other efforts, including the recent Blue Mountains bushfire recovery and Life Without Barriers.

When asked why their faces have to be concealed in photos, one insider said it was because of threats of violence from opposing fans. One member is a serving police officer while another was told by his employer he would be fired if he did not quit the group.