TOWN fear a heavy FA fine and possible closure of parts of the Galpharm Stadium if there is any more missile throwing by their fans.
And club secretary Ann Hough, who has asked supporters to help identify the culprits, has warned she will not hesitate to issue life bans.
Two bottles and a number of coins were hurled on to the pitch at Valley Parade during last Saturday's 1-0 derby win at Bradford.
The FA have asked Bradford, as the host club, for their observations on the incidents, which occurred after the sending off of Town defender Danny Adams 72 minutes into the League I clash.
And Hough hasn't ruled out being called to account by the game's domestic rulers.
"We're concerned, firstly because we don't condone this kind of behaviour in any way, and secondly, because we were twice asked for our comments by the FA after incidents last season," she said.
"We're worried that should there be any further such episodes, the FA will come down heavily on us.
"Their powers are wide-ranging, from a heavy fine to closure of parts of the stadium, or both."
In one incident last season, Brentford player Jay Tabb was felled by a missile thrown by a Town fan.
Hough has studied video footage from Bradford, but it has been inconclusive as to the culprits.
"We're working closely with our safety officer, the police and the FA," she said.
"We are keen to hear from anyone who has any information about the incidents.
"We operate a zero tolerance policy. Anyone found guilty of throwing missiles on to the pitch will be banned for life.
"There is no excuse for it, and a very small minority of what I would hesitate to call our fans are spoiling things for the vast majority.
"We want spectators of all ages to be able to come to our stadium and enjoy matches in a proper family atmosphere."