CROWN POINT, Indiana (CNN) -- More than 2,000 voter registration forms filed in northern Indiana's Lake County by a liberal activist group this week have turned out to be bogus, election officials said Thursday.

An official enters the Las Vegas, Nevada, ACORN office, which is under investigation for alleged voter fraud.

The group -- the Association of Community Organizations for Reform Now, or ACORN -- already faces allegations of filing fraudulent voter registrations in Nevada and faces investigations in other states.

And in Lake County, home to the long-depressed steel town of Gary, the bipartisan Elections Board has stopped processing a stack of about 5,000 applications delivered just before the October 6 registration deadline after the first 2,100 turned out to be phony.

"All the signatures looked exactly the same," Ruthann Hoagland, a Republican on the board. "Everything on the card filled out looks exactly the same."

The forms included registrations submitted in the names of the dead -- and in one case, the name of a fast-food restaurant, Jimmy Johns. Sally LaSota, a Democrat on the board, called the forms fraudulent and said whoever filed them broke the law. Watch how dead people are turning up on voter registration forms »

"ACORN, with its intent, perhaps was good in the beginning, but went awry somewhere," LaSota said.

Over the past four years, a dozen states have investigated complaints of fraudulent registrations filed by ACORN. On Tuesday, Nevada authorities raided an ACORN office in Las Vegas, Nevada, where workers are accused of registering members of the Dallas Cowboys football team. And the group has become the target of Republican attacks on voter fraud, a perennial GOP issue.

A subsidiary of the group was paid $800,000 by Democratic presidential candidate Barack Obama's campaign to register voters for the 2008 primaries, and ACORN's political wing endorsed Obama back in February. But Obama's campaign told CNN that it "is committed to protecting the integrity of the voting process," and said it has not worked with ACORN during the general election.

Brian Mellor, an ACORN attorney in Boston, said the group has its own quality-control process and has fired workers in the past -- including workers in Gary. But he said allegations that his organization committed fraud is a government attempt to keep people disenfranchised. Watch more about this investigation »

"We believe their purpose is to attack ACORN and suppress votes," Mellor said. "We believe that by attacking ACORN, they are going to discourage people that have registered to vote with ACORN from voting."

CNN was unable to reach ACORN officials in Gary and in Milwaukee, Wisconsin, where the group's Indiana operation is based. Offices in both cities were empty when reporters visited.

Lake County elections officials have set aside all 5,000 of the ACORN-submitted applications in what Hoagland called the "fake pile" for later review. But she said every one will be reviewed before the election to make sure no legitimate voters are skipped.

There has been no evidence of voter fraud yet, because voters have yet to go to the polls. But elections officials say they will be sending their information to prosecutors, who will determine whether any investigation will begin.

"We have no idea what the motive behind it is," she said. "It's just overwhelming to us."

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