‘90210’ star Ian Ziering viciously attacked by bikers on Hollywood Blvd.

6:19 PM PST — We’re told an official report has been prepared, naming Ian as a victim. Police have not yet made any arrests and are still investigating the incident.

5:33 PM PST — Law enforcement sources tell TMZ they are aware of the incident and are talking to the parties involved. There is no word yet on whether any arrests will be made.

Ian Ziering was jumped by a bunch of bikers running amok in Los Angeles – a horrifying moment caught on camera… and a terribly bad way to end his year.

The star of ‘Beverly Hills, 90210’ fell into the crosshairs of several assailants driving along Hollywood Blvd on Sunday. on a variety of motorized mini bikes and weaving through traffic… including, it seems, Ian’s vehicle – which we’re told may have been hit.

Ian can be seen jumping out of his car after one of the bikers apparently gets his attention, possibly due to a hit-and-run… and the altercation erupts into a violent brawl, all seen on video obtained by TMZ.

Take a look… Ian begins to wail at the man in question, but he is soon mobbed by the others… who begin to reprimand him mercilessly as he tries to run away. Like we said, the cilp is absolutely bananas… especially considering this is a well-known actor.

We’re told this assault ended when Ian got back in his car and drove away… ditto for the motorcyclists, who got out of there. It doesn’t look like the police were called, so you could say it was left on the street. Not to make light of it, but this nice one is ‘Sharknado’ encoded, isn’t it?