PHOENIX - Just when it seemed the Barack Obama citizenship flap had faded into the background, Maricopa County Sheriff Joe Arpaio has turned the spotlight back on.

On Thursday Arpaio charged the birth certificate Obama says proves he is a U.S. citizen is a fraud, contending a forensic examination of the electronic document posted last year by the White House proves that it was not simply scanned into a file but actually put together in several pieces.

Mike Zullo, head of the sheriff's Cold Case Posse who headed the investigation, said the inconsistencies in the document cannot be explained away by claims it was optimized or had been scanned with optical character-recognition software.

Zullo also said a separate examination proves Obama's 1980 Selective Service registration also is a fake.

The White House, which thought the issue had been put to sleep with the posting of the birth certificate, had no comment.

While saying the evidence proves that a crime was committed, Arpaio was careful not to implicate the president.

"I'm not accusing anyone of anything until we find out who may have committed these alleged crimes over this birth certificate and the Selective Service card," Arpaio said.

Arpaio brushed aside a question of why he was able to find such evidence when no one else in the country has. The sheriff said he probably was the only one who bothered to investigate in detail.

Zullo also said the fact the Honolulu newspaper had a birth announcement at the time proves nothing, saying the newspaper accepted such messages without requiring proof the person actually had been born in the state.

And Zullo insisted Arpaio has jurisdiction.

He said the electronic document put up online by the White House "was a representation made to the people of Maricopa County," he said. "You fraud one person in Maricopa County with that, you fraud every person in Maricopa County."

Zullo stressed, though, "we are not accusing Mr. Obama of creating this document."

"At this juncture, we have advised Sheriff Arpaio we believe there should be a full-blown criminal investigation because a fraud has been committed in Maricopa County and the state of Arizona," Zullo said. "The document is fake. The representations, therefore, are fake."

Arpaio said the investigation was not designed to divert attention from the Justice Department investigation into allegations of racial profiling by his deputies.

It was started before he was notified he was under investigation, Arpaio said.