(CNN) -- Nevada election officials have launched an investigation into allegations that a Republican-led voter registration drive improperly disposed of forms it collected from potential Democratic voters.

Secretary of State Dean Heller said Wednesday that his office was reviewing the allegations, first raised Tuesday in a report by CNN affiliate KLAS-TV in Las Vegas.

"We are researching state and federal law to determine what violations may have occurred," Heller said in a statement. "If, in fact, the allegations are true and federal law has been broken, all efforts will be made to prosecute the individuals and/or the organization responsible."

The probe centers around a private voter registration firm, Voter Outreach of America, which collected registrations from voters in Nevada, a pivotal presidential battleground state. The company was set up by Sproul & Associates Inc., a Republican political consulting firm based in Phoenix, Arizona.

Under Nevada law, private canvassing efforts -- even those run by partisan groups -- must turn in all voter registration forms they collect, regardless of the party affiliation of those registering.

In the KLAS report, a former employee of Voter Outreach, Eric Russell, alleged that he saw a supervisor destroy forms collected from Democratic voters.

KLAS quoted Russell as saying that "we caught her taking Democrats out of my pile, handed them to her assistant, and he ripped them up right in front of us." CNN could not reach Russell for comment.

Heller said that if true, such actions "would be an incredible injustice to people who believe they have registered, only to find out later that their form was tossed away."

But Nathan Sproul, head of Sproul & Associates, disputed the allegations, saying that his company has a "zero tolerance" policy for such conduct and describing Russell as a "disgruntled former employee" who was fired a week ago.

Sproul provided sworn statements from two supervisors who said they turned in all of the collected forms and that none were "discarded, destroyed, tampered with."

However, Sproul, whose firm received nearly $500,000 this election cycle from the Republican Party, said that "it is safe to say we were trying to register Republicans."

In a statement, the Republican National Committee said, "Anyone who engages in fraudulent voter registration activities should be prosecuted to the fullest extent of the law."

The secretary of state advised Nevada voters to call local election officials to confirm their registration before Election Day. Tuesday was the deadline to register.

Jon Summer, a spokesman for the Nevada Democratic State Committee, said the party would file a lawsuit seeking to reopen the registration process for voters whose forms might have been destroyed.

"We don't really know how many victims there are in this case," he said.

A spokesman for Heller, Steve George, said the number of new voters added to Nevada rolls since the 2002 election will be between 200,000 to 350,000.

Nevada's population grew 3.4. percent in the past two years, making it the fast-growing state in the nation, according to the U.S. Census Bureau. President Bush won the state in 2000 by about 22,000 votes.

Voter Outreach of America is also under investigation in Oregon for "alteration and destruction of voter registration cards," said Anne Martens, a spokeswoman for Oregon Secretary of State Bill Bradbury.

She said her office had received numerous complaints since CNN affiliate KGW in Portland broadcast a report spotlighting an out-of-state canvasser who was registering only Republicans.

"That's how I get paid, and I am doing it for the money," said the canvasser, whom KGW identified as Mike Johnson. He said he received $5 per card. The TV report aired Tuesday -- the registration deadline in Oregon.

"We didn't know this was going on until that happened," Martens said. "We're launching a full investigation."

CNN's Dan Lothian and Phil Hirschkorn contributed to this report.

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